golang.org/x/crypto

The golang.org/x/crypto/openpgp package is unsafe by design, has numerous known security issues, is not maintained, and should not be used.

If you are required to interoperate with OpenPGP systems and need a maintained package, consider github.com/ProtonMail/go-crypto/openpgp which is a maintained fork that aims to be a drop-in replacement for this package.

The golang.org/x/crypto/openpgp package is unsafe by design, has numerous known security issues, is not maintained, and should not be used.

If you are required to interoperate with OpenPGP systems and need a maintained package, consider github.com/ProtonMail/go-crypto/openpgp which is a maintained fork that aims to be a drop-in replacement for this package.

Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection.

Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking.

Previously, a channel registered in the mux's chanList is not usable until it is established. A malicious peer was able flood the channel's incomingRequests, deadlocking the entire connection.

Now, we add an atomic established state, set when a channel becomes usable. Until such a time, handlePacket drops every packet other than the open confirmation/failure, without blocking and without tearing down the connection.

The golang.org/x/crypto/openpgp package is unsafe by design, has numerous known security issues, is not maintained, and should not be used.

If you are required to interoperate with OpenPGP systems and need a maintained package, consider github.com/ProtonMail/go-crypto/openpgp which is a maintained fork that aims to be a drop-in replacement for this package.

Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection.

Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking.

Previously, a channel registered in the mux's chanList is not usable until it is established. A malicious peer was able flood the channel's incomingRequests, deadlocking the entire connection.

Now, we add an atomic established state, set when a channel becomes usable. Until such a time, handlePacket drops every packet other than the open confirmation/failure, without blocking and without tearing down the connection.

The source-address critical option in the Permissions returned by an authentication callback was only enforced for the PublicKeyCallback and VerifiedPublicKeyCallback paths, extending the fix for CVE-2026-46595. Permissions returned by the PasswordCallback, KeyboardInteractiveCallback, NoClientAuthCallback, and GSSAPIWithMICConfig.AllowLogin callbacks were not validated against the client's remote address, so a source-address restriction set by those callbacks was silently ignored. The check is now applied to the Permissions returned by any authentication callback.

The golang.org/x/crypto/openpgp package is unsafe by design, has numerous known security issues, is not maintained, and should not be used.

If you are required to interoperate with OpenPGP systems and need a maintained package, consider github.com/ProtonMail/go-crypto/openpgp which is a maintained fork that aims to be a drop-in replacement for this package.

Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection.

Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking.

Previously, a channel registered in the mux's chanList is not usable until it is established. A malicious peer was able flood the channel's incomingRequests, deadlocking the entire connection.

Now, we add an atomic established state, set when a channel becomes usable. Until such a time, handlePacket drops every packet other than the open confirmation/failure, without blocking and without tearing down the connection.

The source-address critical option in the Permissions returned by an authentication callback was only enforced for the PublicKeyCallback and VerifiedPublicKeyCallback paths, extending the fix for CVE-2026-46595. Permissions returned by the PasswordCallback, KeyboardInteractiveCallback, NoClientAuthCallback, and GSSAPIWithMICConfig.AllowLogin callbacks were not validated against the client's remote address, so a source-address restriction set by those callbacks was silently ignored. The check is now applied to the Permissions returned by any authentication callback.

The golang.org/x/crypto/openpgp package is unsafe by design, has numerous known security issues, is not maintained, and should not be used.

If you are required to interoperate with OpenPGP systems and need a maintained package, consider github.com/ProtonMail/go-crypto/openpgp which is a maintained fork that aims to be a drop-in replacement for this package.

Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection.

Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking.

Previously, a channel registered in the mux's chanList is not usable until it is established. A malicious peer was able flood the channel's incomingRequests, deadlocking the entire connection.

Now, we add an atomic established state, set when a channel becomes usable. Until such a time, handlePacket drops every packet other than the open confirmation/failure, without blocking and without tearing down the connection.

The source-address critical option in the Permissions returned by an authentication callback was only enforced for the PublicKeyCallback and VerifiedPublicKeyCallback paths, extending the fix for CVE-2026-46595. Permissions returned by the PasswordCallback, KeyboardInteractiveCallback, NoClientAuthCallback, and GSSAPIWithMICConfig.AllowLogin callbacks were not validated against the client's remote address, so a source-address restriction set by those callbacks was silently ignored. The check is now applied to the Permissions returned by any authentication callback.

The golang.org/x/crypto/openpgp package is unsafe by design, has numerous known security issues, is not maintained, and should not be used.

If you are required to interoperate with OpenPGP systems and need a maintained package, consider github.com/ProtonMail/go-crypto/openpgp which is a maintained fork that aims to be a drop-in replacement for this package.

Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection.

Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking.

Previously, a channel registered in the mux's chanList is not usable until it is established. A malicious peer was able flood the channel's incomingRequests, deadlocking the entire connection.

Now, we add an atomic established state, set when a channel becomes usable. Until such a time, handlePacket drops every packet other than the open confirmation/failure, without blocking and without tearing down the connection.

The source-address critical option in the Permissions returned by an authentication callback was only enforced for the PublicKeyCallback and VerifiedPublicKeyCallback paths, extending the fix for CVE-2026-46595. Permissions returned by the PasswordCallback, KeyboardInteractiveCallback, NoClientAuthCallback, and GSSAPIWithMICConfig.AllowLogin callbacks were not validated against the client's remote address, so a source-address restriction set by those callbacks was silently ignored. The check is now applied to the Permissions returned by any authentication callback.

The golang.org/x/crypto/openpgp package is unsafe by design, has numerous known security issues, is not maintained, and should not be used.

If you are required to interoperate with OpenPGP systems and need a maintained package, consider github.com/ProtonMail/go-crypto/openpgp which is a maintained fork that aims to be a drop-in replacement for this package.

Previously, CVE-2024-45337 fixed an authorization bypass for misused ssh server configurations; if any other type of callback is passed other than public key, then the source-address validation would be skipped.

Previously, a revoked 'SignatureKey' belonging to a CA was not correctly checked for revocation. Now, both the 'key' and 'key.SignatureKey' are checked for @revoked.

When writing data larger than 4GB in a single Write call on an SSH channel, an integer overflow in the internal payload size calculation caused the write loop to spin indefinitely, sending empty packets without making progress. The size comparison now uses int64 to prevent truncation.

The Verify() method for FIDO/U2F security key types (sk-ecdsa-sha2-nistp256@openssh.com, sk-ssh-ed25519@openssh.com) did not check the User Presence flag. Signatures generated without physical touch were accepted, allowing unattended use of a hardware security key. To restore the previous behavior, return a "no-touch-required" extension in Permissions.Extensions from PublicKeyCallback.

The RSA and DSA public key parsers did not enforce size limits on key parameters. A crafted public key with an excessively large modulus or DSA parameter could cause several minutes of CPU consumption during signature verification. This could be triggered by unauthenticated clients during public key authentication. RSA moduli are now limited to 8192 bits, and DSA parameters are validated per FIPS 186-2.

A malicious SSH peer could send unsolicited global request responses to fill an internal buffer, blocking the connection's read loop. The blocked goroutine could not be released by calling Close(), resulting in a resource leak per connection. Unsolicited global responses are now discarded.

An authenticated SSH client that repeatedly opened channels which were rejected by the server caused unbounded memory growth, eventually crashing the server process and affecting all connected users. Rejected channels are now properly removed from the connection's internal state and released for garbage collection.

SSH servers which use CertChecker as a public key callback without setting IsUserAuthority or IsHostAuthority could be caused to panic by a client presenting a certificate. CertChecker now returns an error instead of panicking when these callbacks are nil.

When an SSH server authentication callback returned PartialSuccessError with non-nil Permissions, those permissions were silently discarded, potentially dropping certificate restrictions such as force-command after a second factor succeeded. Returning non-nil Permissions with PartialSuccessError now results in a connection error.

An incorrectly placed cast from bytes to int allowed for server-side panic in the AES-GCM packet decoder for well-crafted inputs.

When adding a key to a remote agent constraint extensions such as restrict-destination-v00@openssh.com were not serialized in the request. Destination restrictions were silently stripped when forwarding keys, allowing unrestricted use of the key on the remote host. The client now serializes all constraint extensions. Additionally, the in-memory keyring returned by NewKeyring() now rejects keys with unsupported constraint extensions instead of silently ignoring them.

The in-memory keyring returned by NewKeyring() silently accepted keys with the ConfirmBeforeUse constraint but never enforced it. The key would sign without any confirmation prompt, with no indication to the caller that the constraint was not in effect. NewKeyring() now returns an error when unsupported constraints are requested.

For certain crafted inputs, a 'ed25519.PrivateKey' was created by casting malformed wire bytes, leading to a panic when used.

Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection.

Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking.

Previously, a channel registered in the mux's chanList is not usable until it is established. A malicious peer was able flood the channel's incomingRequests, deadlocking the entire connection.

Now, we add an atomic established state, set when a channel becomes usable. Until such a time, handlePacket drops every packet other than the open confirmation/failure, without blocking and without tearing down the connection.

The source-address critical option in the Permissions returned by an authentication callback was only enforced for the PublicKeyCallback and VerifiedPublicKeyCallback paths, extending the fix for CVE-2026-46595. Permissions returned by the PasswordCallback, KeyboardInteractiveCallback, NoClientAuthCallback, and GSSAPIWithMICConfig.AllowLogin callbacks were not validated against the client's remote address, so a source-address restriction set by those callbacks was silently ignored. The check is now applied to the Permissions returned by any authentication callback.

The golang.org/x/crypto/openpgp package is unsafe by design, has numerous known security issues, is not maintained, and should not be used.

If you are required to interoperate with OpenPGP systems and need a maintained package, consider github.com/ProtonMail/go-crypto/openpgp which is a maintained fork that aims to be a drop-in replacement for this package.

Previously, CVE-2024-45337 fixed an authorization bypass for misused ssh server configurations; if any other type of callback is passed other than public key, then the source-address validation would be skipped.

Previously, a revoked 'SignatureKey' belonging to a CA was not correctly checked for revocation. Now, both the 'key' and 'key.SignatureKey' are checked for @revoked.

When writing data larger than 4GB in a single Write call on an SSH channel, an integer overflow in the internal payload size calculation caused the write loop to spin indefinitely, sending empty packets without making progress. The size comparison now uses int64 to prevent truncation.

The Verify() method for FIDO/U2F security key types (sk-ecdsa-sha2-nistp256@openssh.com, sk-ssh-ed25519@openssh.com) did not check the User Presence flag. Signatures generated without physical touch were accepted, allowing unattended use of a hardware security key. To restore the previous behavior, return a "no-touch-required" extension in Permissions.Extensions from PublicKeyCallback.

The RSA and DSA public key parsers did not enforce size limits on key parameters. A crafted public key with an excessively large modulus or DSA parameter could cause several minutes of CPU consumption during signature verification. This could be triggered by unauthenticated clients during public key authentication. RSA moduli are now limited to 8192 bits, and DSA parameters are validated per FIPS 186-2.

A malicious SSH peer could send unsolicited global request responses to fill an internal buffer, blocking the connection's read loop. The blocked goroutine could not be released by calling Close(), resulting in a resource leak per connection. Unsolicited global responses are now discarded.

An authenticated SSH client that repeatedly opened channels which were rejected by the server caused unbounded memory growth, eventually crashing the server process and affecting all connected users. Rejected channels are now properly removed from the connection's internal state and released for garbage collection.

SSH servers which use CertChecker as a public key callback without setting IsUserAuthority or IsHostAuthority could be caused to panic by a client presenting a certificate. CertChecker now returns an error instead of panicking when these callbacks are nil.

When an SSH server authentication callback returned PartialSuccessError with non-nil Permissions, those permissions were silently discarded, potentially dropping certificate restrictions such as force-command after a second factor succeeded. Returning non-nil Permissions with PartialSuccessError now results in a connection error.

An incorrectly placed cast from bytes to int allowed for server-side panic in the AES-GCM packet decoder for well-crafted inputs.

When adding a key to a remote agent constraint extensions such as restrict-destination-v00@openssh.com were not serialized in the request. Destination restrictions were silently stripped when forwarding keys, allowing unrestricted use of the key on the remote host. The client now serializes all constraint extensions. Additionally, the in-memory keyring returned by NewKeyring() now rejects keys with unsupported constraint extensions instead of silently ignoring them.

The in-memory keyring returned by NewKeyring() silently accepted keys with the ConfirmBeforeUse constraint but never enforced it. The key would sign without any confirmation prompt, with no indication to the caller that the constraint was not in effect. NewKeyring() now returns an error when unsupported constraints are requested.

For certain crafted inputs, a 'ed25519.PrivateKey' was created by casting malformed wire bytes, leading to a panic when used.

Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection.

Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking.

Previously, a channel registered in the mux's chanList is not usable until it is established. A malicious peer was able flood the channel's incomingRequests, deadlocking the entire connection.

Now, we add an atomic established state, set when a channel becomes usable. Until such a time, handlePacket drops every packet other than the open confirmation/failure, without blocking and without tearing down the connection.

The source-address critical option in the Permissions returned by an authentication callback was only enforced for the PublicKeyCallback and VerifiedPublicKeyCallback paths, extending the fix for CVE-2026-46595. Permissions returned by the PasswordCallback, KeyboardInteractiveCallback, NoClientAuthCallback, and GSSAPIWithMICConfig.AllowLogin callbacks were not validated against the client's remote address, so a source-address restriction set by those callbacks was silently ignored. The check is now applied to the Permissions returned by any authentication callback.

The golang.org/x/crypto/openpgp package is unsafe by design, has numerous known security issues, is not maintained, and should not be used.

If you are required to interoperate with OpenPGP systems and need a maintained package, consider github.com/ProtonMail/go-crypto/openpgp which is a maintained fork that aims to be a drop-in replacement for this package.

Previously, CVE-2024-45337 fixed an authorization bypass for misused ssh server configurations; if any other type of callback is passed other than public key, then the source-address validation would be skipped.

Previously, a revoked 'SignatureKey' belonging to a CA was not correctly checked for revocation. Now, both the 'key' and 'key.SignatureKey' are checked for @revoked.

When writing data larger than 4GB in a single Write call on an SSH channel, an integer overflow in the internal payload size calculation caused the write loop to spin indefinitely, sending empty packets without making progress. The size comparison now uses int64 to prevent truncation.

The Verify() method for FIDO/U2F security key types (sk-ecdsa-sha2-nistp256@openssh.com, sk-ssh-ed25519@openssh.com) did not check the User Presence flag. Signatures generated without physical touch were accepted, allowing unattended use of a hardware security key. To restore the previous behavior, return a "no-touch-required" extension in Permissions.Extensions from PublicKeyCallback.

The RSA and DSA public key parsers did not enforce size limits on key parameters. A crafted public key with an excessively large modulus or DSA parameter could cause several minutes of CPU consumption during signature verification. This could be triggered by unauthenticated clients during public key authentication. RSA moduli are now limited to 8192 bits, and DSA parameters are validated per FIPS 186-2.

A malicious SSH peer could send unsolicited global request responses to fill an internal buffer, blocking the connection's read loop. The blocked goroutine could not be released by calling Close(), resulting in a resource leak per connection. Unsolicited global responses are now discarded.

An authenticated SSH client that repeatedly opened channels which were rejected by the server caused unbounded memory growth, eventually crashing the server process and affecting all connected users. Rejected channels are now properly removed from the connection's internal state and released for garbage collection.

SSH servers which use CertChecker as a public key callback without setting IsUserAuthority or IsHostAuthority could be caused to panic by a client presenting a certificate. CertChecker now returns an error instead of panicking when these callbacks are nil.

When an SSH server authentication callback returned PartialSuccessError with non-nil Permissions, those permissions were silently discarded, potentially dropping certificate restrictions such as force-command after a second factor succeeded. Returning non-nil Permissions with PartialSuccessError now results in a connection error.

An incorrectly placed cast from bytes to int allowed for server-side panic in the AES-GCM packet decoder for well-crafted inputs.

When adding a key to a remote agent constraint extensions such as restrict-destination-v00@openssh.com were not serialized in the request. Destination restrictions were silently stripped when forwarding keys, allowing unrestricted use of the key on the remote host. The client now serializes all constraint extensions. Additionally, the in-memory keyring returned by NewKeyring() now rejects keys with unsupported constraint extensions instead of silently ignoring them.

The in-memory keyring returned by NewKeyring() silently accepted keys with the ConfirmBeforeUse constraint but never enforced it. The key would sign without any confirmation prompt, with no indication to the caller that the constraint was not in effect. NewKeyring() now returns an error when unsupported constraints are requested.

For certain crafted inputs, a 'ed25519.PrivateKey' was created by casting malformed wire bytes, leading to a panic when used.

Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection.

Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking.

Previously, a channel registered in the mux's chanList is not usable until it is established. A malicious peer was able flood the channel's incomingRequests, deadlocking the entire connection.

Now, we add an atomic established state, set when a channel becomes usable. Until such a time, handlePacket drops every packet other than the open confirmation/failure, without blocking and without tearing down the connection.

The source-address critical option in the Permissions returned by an authentication callback was only enforced for the PublicKeyCallback and VerifiedPublicKeyCallback paths, extending the fix for CVE-2026-46595. Permissions returned by the PasswordCallback, KeyboardInteractiveCallback, NoClientAuthCallback, and GSSAPIWithMICConfig.AllowLogin callbacks were not validated against the client's remote address, so a source-address restriction set by those callbacks was silently ignored. The check is now applied to the Permissions returned by any authentication callback.

The golang.org/x/crypto/openpgp package is unsafe by design, has numerous known security issues, is not maintained, and should not be used.

If you are required to interoperate with OpenPGP systems and need a maintained package, consider github.com/ProtonMail/go-crypto/openpgp which is a maintained fork that aims to be a drop-in replacement for this package.

Previously, CVE-2024-45337 fixed an authorization bypass for misused ssh server configurations; if any other type of callback is passed other than public key, then the source-address validation would be skipped.

Previously, a revoked 'SignatureKey' belonging to a CA was not correctly checked for revocation. Now, both the 'key' and 'key.SignatureKey' are checked for @revoked.

When writing data larger than 4GB in a single Write call on an SSH channel, an integer overflow in the internal payload size calculation caused the write loop to spin indefinitely, sending empty packets without making progress. The size comparison now uses int64 to prevent truncation.

The Verify() method for FIDO/U2F security key types (sk-ecdsa-sha2-nistp256@openssh.com, sk-ssh-ed25519@openssh.com) did not check the User Presence flag. Signatures generated without physical touch were accepted, allowing unattended use of a hardware security key. To restore the previous behavior, return a "no-touch-required" extension in Permissions.Extensions from PublicKeyCallback.

The RSA and DSA public key parsers did not enforce size limits on key parameters. A crafted public key with an excessively large modulus or DSA parameter could cause several minutes of CPU consumption during signature verification. This could be triggered by unauthenticated clients during public key authentication. RSA moduli are now limited to 8192 bits, and DSA parameters are validated per FIPS 186-2.

A malicious SSH peer could send unsolicited global request responses to fill an internal buffer, blocking the connection's read loop. The blocked goroutine could not be released by calling Close(), resulting in a resource leak per connection. Unsolicited global responses are now discarded.

An authenticated SSH client that repeatedly opened channels which were rejected by the server caused unbounded memory growth, eventually crashing the server process and affecting all connected users. Rejected channels are now properly removed from the connection's internal state and released for garbage collection.

SSH servers which use CertChecker as a public key callback without setting IsUserAuthority or IsHostAuthority could be caused to panic by a client presenting a certificate. CertChecker now returns an error instead of panicking when these callbacks are nil.

When an SSH server authentication callback returned PartialSuccessError with non-nil Permissions, those permissions were silently discarded, potentially dropping certificate restrictions such as force-command after a second factor succeeded. Returning non-nil Permissions with PartialSuccessError now results in a connection error.

An incorrectly placed cast from bytes to int allowed for server-side panic in the AES-GCM packet decoder for well-crafted inputs.

When adding a key to a remote agent constraint extensions such as restrict-destination-v00@openssh.com were not serialized in the request. Destination restrictions were silently stripped when forwarding keys, allowing unrestricted use of the key on the remote host. The client now serializes all constraint extensions. Additionally, the in-memory keyring returned by NewKeyring() now rejects keys with unsupported constraint extensions instead of silently ignoring them.

The in-memory keyring returned by NewKeyring() silently accepted keys with the ConfirmBeforeUse constraint but never enforced it. The key would sign without any confirmation prompt, with no indication to the caller that the constraint was not in effect. NewKeyring() now returns an error when unsupported constraints are requested.

For certain crafted inputs, a 'ed25519.PrivateKey' was created by casting malformed wire bytes, leading to a panic when used.

Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection.

Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking.

Previously, a channel registered in the mux's chanList is not usable until it is established. A malicious peer was able flood the channel's incomingRequests, deadlocking the entire connection.

Now, we add an atomic established state, set when a channel becomes usable. Until such a time, handlePacket drops every packet other than the open confirmation/failure, without blocking and without tearing down the connection.

The source-address critical option in the Permissions returned by an authentication callback was only enforced for the PublicKeyCallback and VerifiedPublicKeyCallback paths, extending the fix for CVE-2026-46595. Permissions returned by the PasswordCallback, KeyboardInteractiveCallback, NoClientAuthCallback, and GSSAPIWithMICConfig.AllowLogin callbacks were not validated against the client's remote address, so a source-address restriction set by those callbacks was silently ignored. The check is now applied to the Permissions returned by any authentication callback.

The golang.org/x/crypto/openpgp package is unsafe by design, has numerous known security issues, is not maintained, and should not be used.

If you are required to interoperate with OpenPGP systems and need a maintained package, consider github.com/ProtonMail/go-crypto/openpgp which is a maintained fork that aims to be a drop-in replacement for this package.

Previously, CVE-2024-45337 fixed an authorization bypass for misused ssh server configurations; if any other type of callback is passed other than public key, then the source-address validation would be skipped.

Previously, a revoked 'SignatureKey' belonging to a CA was not correctly checked for revocation. Now, both the 'key' and 'key.SignatureKey' are checked for @revoked.

When writing data larger than 4GB in a single Write call on an SSH channel, an integer overflow in the internal payload size calculation caused the write loop to spin indefinitely, sending empty packets without making progress. The size comparison now uses int64 to prevent truncation.

The Verify() method for FIDO/U2F security key types (sk-ecdsa-sha2-nistp256@openssh.com, sk-ssh-ed25519@openssh.com) did not check the User Presence flag. Signatures generated without physical touch were accepted, allowing unattended use of a hardware security key. To restore the previous behavior, return a "no-touch-required" extension in Permissions.Extensions from PublicKeyCallback.

The RSA and DSA public key parsers did not enforce size limits on key parameters. A crafted public key with an excessively large modulus or DSA parameter could cause several minutes of CPU consumption during signature verification. This could be triggered by unauthenticated clients during public key authentication. RSA moduli are now limited to 8192 bits, and DSA parameters are validated per FIPS 186-2.

A malicious SSH peer could send unsolicited global request responses to fill an internal buffer, blocking the connection's read loop. The blocked goroutine could not be released by calling Close(), resulting in a resource leak per connection. Unsolicited global responses are now discarded.

An authenticated SSH client that repeatedly opened channels which were rejected by the server caused unbounded memory growth, eventually crashing the server process and affecting all connected users. Rejected channels are now properly removed from the connection's internal state and released for garbage collection.

SSH servers which use CertChecker as a public key callback without setting IsUserAuthority or IsHostAuthority could be caused to panic by a client presenting a certificate. CertChecker now returns an error instead of panicking when these callbacks are nil.

When an SSH server authentication callback returned PartialSuccessError with non-nil Permissions, those permissions were silently discarded, potentially dropping certificate restrictions such as force-command after a second factor succeeded. Returning non-nil Permissions with PartialSuccessError now results in a connection error.

An incorrectly placed cast from bytes to int allowed for server-side panic in the AES-GCM packet decoder for well-crafted inputs.

When adding a key to a remote agent constraint extensions such as restrict-destination-v00@openssh.com were not serialized in the request. Destination restrictions were silently stripped when forwarding keys, allowing unrestricted use of the key on the remote host. The client now serializes all constraint extensions. Additionally, the in-memory keyring returned by NewKeyring() now rejects keys with unsupported constraint extensions instead of silently ignoring them.

The in-memory keyring returned by NewKeyring() silently accepted keys with the ConfirmBeforeUse constraint but never enforced it. The key would sign without any confirmation prompt, with no indication to the caller that the constraint was not in effect. NewKeyring() now returns an error when unsupported constraints are requested.

For certain crafted inputs, a 'ed25519.PrivateKey' was created by casting malformed wire bytes, leading to a panic when used.

Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection.

Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking.

Previously, a channel registered in the mux's chanList is not usable until it is established. A malicious peer was able flood the channel's incomingRequests, deadlocking the entire connection.

Now, we add an atomic established state, set when a channel becomes usable. Until such a time, handlePacket drops every packet other than the open confirmation/failure, without blocking and without tearing down the connection.

The source-address critical option in the Permissions returned by an authentication callback was only enforced for the PublicKeyCallback and VerifiedPublicKeyCallback paths, extending the fix for CVE-2026-46595. Permissions returned by the PasswordCallback, KeyboardInteractiveCallback, NoClientAuthCallback, and GSSAPIWithMICConfig.AllowLogin callbacks were not validated against the client's remote address, so a source-address restriction set by those callbacks was silently ignored. The check is now applied to the Permissions returned by any authentication callback.

The golang.org/x/crypto/openpgp package is unsafe by design, has numerous known security issues, is not maintained, and should not be used.

If you are required to interoperate with OpenPGP systems and need a maintained package, consider github.com/ProtonMail/go-crypto/openpgp which is a maintained fork that aims to be a drop-in replacement for this package.

Previously, CVE-2024-45337 fixed an authorization bypass for misused ssh server configurations; if any other type of callback is passed other than public key, then the source-address validation would be skipped.

Previously, a revoked 'SignatureKey' belonging to a CA was not correctly checked for revocation. Now, both the 'key' and 'key.SignatureKey' are checked for @revoked.

When writing data larger than 4GB in a single Write call on an SSH channel, an integer overflow in the internal payload size calculation caused the write loop to spin indefinitely, sending empty packets without making progress. The size comparison now uses int64 to prevent truncation.

The Verify() method for FIDO/U2F security key types (sk-ecdsa-sha2-nistp256@openssh.com, sk-ssh-ed25519@openssh.com) did not check the User Presence flag. Signatures generated without physical touch were accepted, allowing unattended use of a hardware security key. To restore the previous behavior, return a "no-touch-required" extension in Permissions.Extensions from PublicKeyCallback.

The RSA and DSA public key parsers did not enforce size limits on key parameters. A crafted public key with an excessively large modulus or DSA parameter could cause several minutes of CPU consumption during signature verification. This could be triggered by unauthenticated clients during public key authentication. RSA moduli are now limited to 8192 bits, and DSA parameters are validated per FIPS 186-2.

A malicious SSH peer could send unsolicited global request responses to fill an internal buffer, blocking the connection's read loop. The blocked goroutine could not be released by calling Close(), resulting in a resource leak per connection. Unsolicited global responses are now discarded.

An authenticated SSH client that repeatedly opened channels which were rejected by the server caused unbounded memory growth, eventually crashing the server process and affecting all connected users. Rejected channels are now properly removed from the connection's internal state and released for garbage collection.

SSH servers which use CertChecker as a public key callback without setting IsUserAuthority or IsHostAuthority could be caused to panic by a client presenting a certificate. CertChecker now returns an error instead of panicking when these callbacks are nil.

When an SSH server authentication callback returned PartialSuccessError with non-nil Permissions, those permissions were silently discarded, potentially dropping certificate restrictions such as force-command after a second factor succeeded. Returning non-nil Permissions with PartialSuccessError now results in a connection error.

An incorrectly placed cast from bytes to int allowed for server-side panic in the AES-GCM packet decoder for well-crafted inputs.

When adding a key to a remote agent constraint extensions such as restrict-destination-v00@openssh.com were not serialized in the request. Destination restrictions were silently stripped when forwarding keys, allowing unrestricted use of the key on the remote host. The client now serializes all constraint extensions. Additionally, the in-memory keyring returned by NewKeyring() now rejects keys with unsupported constraint extensions instead of silently ignoring them.

The in-memory keyring returned by NewKeyring() silently accepted keys with the ConfirmBeforeUse constraint but never enforced it. The key would sign without any confirmation prompt, with no indication to the caller that the constraint was not in effect. NewKeyring() now returns an error when unsupported constraints are requested.

For certain crafted inputs, a 'ed25519.PrivateKey' was created by casting malformed wire bytes, leading to a panic when used.

Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection.

Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking.

Previously, a channel registered in the mux's chanList is not usable until it is established. A malicious peer was able flood the channel's incomingRequests, deadlocking the entire connection.

Now, we add an atomic established state, set when a channel becomes usable. Until such a time, handlePacket drops every packet other than the open confirmation/failure, without blocking and without tearing down the connection.

The source-address critical option in the Permissions returned by an authentication callback was only enforced for the PublicKeyCallback and VerifiedPublicKeyCallback paths, extending the fix for CVE-2026-46595. Permissions returned by the PasswordCallback, KeyboardInteractiveCallback, NoClientAuthCallback, and GSSAPIWithMICConfig.AllowLogin callbacks were not validated against the client's remote address, so a source-address restriction set by those callbacks was silently ignored. The check is now applied to the Permissions returned by any authentication callback.

The golang.org/x/crypto/openpgp package is unsafe by design, has numerous known security issues, is not maintained, and should not be used.

If you are required to interoperate with OpenPGP systems and need a maintained package, consider github.com/ProtonMail/go-crypto/openpgp which is a maintained fork that aims to be a drop-in replacement for this package.

Previously, CVE-2024-45337 fixed an authorization bypass for misused ssh server configurations; if any other type of callback is passed other than public key, then the source-address validation would be skipped.

Previously, a revoked 'SignatureKey' belonging to a CA was not correctly checked for revocation. Now, both the 'key' and 'key.SignatureKey' are checked for @revoked.

When writing data larger than 4GB in a single Write call on an SSH channel, an integer overflow in the internal payload size calculation caused the write loop to spin indefinitely, sending empty packets without making progress. The size comparison now uses int64 to prevent truncation.

The Verify() method for FIDO/U2F security key types (sk-ecdsa-sha2-nistp256@openssh.com, sk-ssh-ed25519@openssh.com) did not check the User Presence flag. Signatures generated without physical touch were accepted, allowing unattended use of a hardware security key. To restore the previous behavior, return a "no-touch-required" extension in Permissions.Extensions from PublicKeyCallback.

The RSA and DSA public key parsers did not enforce size limits on key parameters. A crafted public key with an excessively large modulus or DSA parameter could cause several minutes of CPU consumption during signature verification. This could be triggered by unauthenticated clients during public key authentication. RSA moduli are now limited to 8192 bits, and DSA parameters are validated per FIPS 186-2.

A malicious SSH peer could send unsolicited global request responses to fill an internal buffer, blocking the connection's read loop. The blocked goroutine could not be released by calling Close(), resulting in a resource leak per connection. Unsolicited global responses are now discarded.

An authenticated SSH client that repeatedly opened channels which were rejected by the server caused unbounded memory growth, eventually crashing the server process and affecting all connected users. Rejected channels are now properly removed from the connection's internal state and released for garbage collection.

SSH servers which use CertChecker as a public key callback without setting IsUserAuthority or IsHostAuthority could be caused to panic by a client presenting a certificate. CertChecker now returns an error instead of panicking when these callbacks are nil.

When an SSH server authentication callback returned PartialSuccessError with non-nil Permissions, those permissions were silently discarded, potentially dropping certificate restrictions such as force-command after a second factor succeeded. Returning non-nil Permissions with PartialSuccessError now results in a connection error.

An incorrectly placed cast from bytes to int allowed for server-side panic in the AES-GCM packet decoder for well-crafted inputs.

When adding a key to a remote agent constraint extensions such as restrict-destination-v00@openssh.com were not serialized in the request. Destination restrictions were silently stripped when forwarding keys, allowing unrestricted use of the key on the remote host. The client now serializes all constraint extensions. Additionally, the in-memory keyring returned by NewKeyring() now rejects keys with unsupported constraint extensions instead of silently ignoring them.

The in-memory keyring returned by NewKeyring() silently accepted keys with the ConfirmBeforeUse constraint but never enforced it. The key would sign without any confirmation prompt, with no indication to the caller that the constraint was not in effect. NewKeyring() now returns an error when unsupported constraints are requested.

For certain crafted inputs, a 'ed25519.PrivateKey' was created by casting malformed wire bytes, leading to a panic when used.

Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection.

Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking.

Previously, a channel registered in the mux's chanList is not usable until it is established. A malicious peer was able flood the channel's incomingRequests, deadlocking the entire connection.

Now, we add an atomic established state, set when a channel becomes usable. Until such a time, handlePacket drops every packet other than the open confirmation/failure, without blocking and without tearing down the connection.

The source-address critical option in the Permissions returned by an authentication callback was only enforced for the PublicKeyCallback and VerifiedPublicKeyCallback paths, extending the fix for CVE-2026-46595. Permissions returned by the PasswordCallback, KeyboardInteractiveCallback, NoClientAuthCallback, and GSSAPIWithMICConfig.AllowLogin callbacks were not validated against the client's remote address, so a source-address restriction set by those callbacks was silently ignored. The check is now applied to the Permissions returned by any authentication callback.

The golang.org/x/crypto/openpgp package is unsafe by design, has numerous known security issues, is not maintained, and should not be used.

If you are required to interoperate with OpenPGP systems and need a maintained package, consider github.com/ProtonMail/go-crypto/openpgp which is a maintained fork that aims to be a drop-in replacement for this package.

Previously, CVE-2024-45337 fixed an authorization bypass for misused ssh server configurations; if any other type of callback is passed other than public key, then the source-address validation would be skipped.

Previously, a revoked 'SignatureKey' belonging to a CA was not correctly checked for revocation. Now, both the 'key' and 'key.SignatureKey' are checked for @revoked.

When writing data larger than 4GB in a single Write call on an SSH channel, an integer overflow in the internal payload size calculation caused the write loop to spin indefinitely, sending empty packets without making progress. The size comparison now uses int64 to prevent truncation.

The Verify() method for FIDO/U2F security key types (sk-ecdsa-sha2-nistp256@openssh.com, sk-ssh-ed25519@openssh.com) did not check the User Presence flag. Signatures generated without physical touch were accepted, allowing unattended use of a hardware security key. To restore the previous behavior, return a "no-touch-required" extension in Permissions.Extensions from PublicKeyCallback.

The RSA and DSA public key parsers did not enforce size limits on key parameters. A crafted public key with an excessively large modulus or DSA parameter could cause several minutes of CPU consumption during signature verification. This could be triggered by unauthenticated clients during public key authentication. RSA moduli are now limited to 8192 bits, and DSA parameters are validated per FIPS 186-2.

A malicious SSH peer could send unsolicited global request responses to fill an internal buffer, blocking the connection's read loop. The blocked goroutine could not be released by calling Close(), resulting in a resource leak per connection. Unsolicited global responses are now discarded.

An authenticated SSH client that repeatedly opened channels which were rejected by the server caused unbounded memory growth, eventually crashing the server process and affecting all connected users. Rejected channels are now properly removed from the connection's internal state and released for garbage collection.

SSH servers which use CertChecker as a public key callback without setting IsUserAuthority or IsHostAuthority could be caused to panic by a client presenting a certificate. CertChecker now returns an error instead of panicking when these callbacks are nil.

When an SSH server authentication callback returned PartialSuccessError with non-nil Permissions, those permissions were silently discarded, potentially dropping certificate restrictions such as force-command after a second factor succeeded. Returning non-nil Permissions with PartialSuccessError now results in a connection error.

An incorrectly placed cast from bytes to int allowed for server-side panic in the AES-GCM packet decoder for well-crafted inputs.

When adding a key to a remote agent constraint extensions such as restrict-destination-v00@openssh.com were not serialized in the request. Destination restrictions were silently stripped when forwarding keys, allowing unrestricted use of the key on the remote host. The client now serializes all constraint extensions. Additionally, the in-memory keyring returned by NewKeyring() now rejects keys with unsupported constraint extensions instead of silently ignoring them.

The in-memory keyring returned by NewKeyring() silently accepted keys with the ConfirmBeforeUse constraint but never enforced it. The key would sign without any confirmation prompt, with no indication to the caller that the constraint was not in effect. NewKeyring() now returns an error when unsupported constraints are requested.

For certain crafted inputs, a 'ed25519.PrivateKey' was created by casting malformed wire bytes, leading to a panic when used.

SSH Agent servers do not validate the size of messages when processing new identity requests, which may cause the program to panic if the message is malformed due to an out of bounds read.

SSH servers parsing GSSAPI authentication requests do not validate the number of mechanisms specified in the request, allowing an attacker to cause unbounded memory consumption.

Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection.

Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking.

Previously, a channel registered in the mux's chanList is not usable until it is established. A malicious peer was able flood the channel's incomingRequests, deadlocking the entire connection.

Now, we add an atomic established state, set when a channel becomes usable. Until such a time, handlePacket drops every packet other than the open confirmation/failure, without blocking and without tearing down the connection.

The source-address critical option in the Permissions returned by an authentication callback was only enforced for the PublicKeyCallback and VerifiedPublicKeyCallback paths, extending the fix for CVE-2026-46595. Permissions returned by the PasswordCallback, KeyboardInteractiveCallback, NoClientAuthCallback, and GSSAPIWithMICConfig.AllowLogin callbacks were not validated against the client's remote address, so a source-address restriction set by those callbacks was silently ignored. The check is now applied to the Permissions returned by any authentication callback.

The golang.org/x/crypto/openpgp package is unsafe by design, has numerous known security issues, is not maintained, and should not be used.

If you are required to interoperate with OpenPGP systems and need a maintained package, consider github.com/ProtonMail/go-crypto/openpgp which is a maintained fork that aims to be a drop-in replacement for this package.

Previously, CVE-2024-45337 fixed an authorization bypass for misused ssh server configurations; if any other type of callback is passed other than public key, then the source-address validation would be skipped.

Previously, a revoked 'SignatureKey' belonging to a CA was not correctly checked for revocation. Now, both the 'key' and 'key.SignatureKey' are checked for @revoked.

When writing data larger than 4GB in a single Write call on an SSH channel, an integer overflow in the internal payload size calculation caused the write loop to spin indefinitely, sending empty packets without making progress. The size comparison now uses int64 to prevent truncation.

The Verify() method for FIDO/U2F security key types (sk-ecdsa-sha2-nistp256@openssh.com, sk-ssh-ed25519@openssh.com) did not check the User Presence flag. Signatures generated without physical touch were accepted, allowing unattended use of a hardware security key. To restore the previous behavior, return a "no-touch-required" extension in Permissions.Extensions from PublicKeyCallback.

The RSA and DSA public key parsers did not enforce size limits on key parameters. A crafted public key with an excessively large modulus or DSA parameter could cause several minutes of CPU consumption during signature verification. This could be triggered by unauthenticated clients during public key authentication. RSA moduli are now limited to 8192 bits, and DSA parameters are validated per FIPS 186-2.

A malicious SSH peer could send unsolicited global request responses to fill an internal buffer, blocking the connection's read loop. The blocked goroutine could not be released by calling Close(), resulting in a resource leak per connection. Unsolicited global responses are now discarded.

An authenticated SSH client that repeatedly opened channels which were rejected by the server caused unbounded memory growth, eventually crashing the server process and affecting all connected users. Rejected channels are now properly removed from the connection's internal state and released for garbage collection.

SSH servers which use CertChecker as a public key callback without setting IsUserAuthority or IsHostAuthority could be caused to panic by a client presenting a certificate. CertChecker now returns an error instead of panicking when these callbacks are nil.

When an SSH server authentication callback returned PartialSuccessError with non-nil Permissions, those permissions were silently discarded, potentially dropping certificate restrictions such as force-command after a second factor succeeded. Returning non-nil Permissions with PartialSuccessError now results in a connection error.

An incorrectly placed cast from bytes to int allowed for server-side panic in the AES-GCM packet decoder for well-crafted inputs.

When adding a key to a remote agent constraint extensions such as restrict-destination-v00@openssh.com were not serialized in the request. Destination restrictions were silently stripped when forwarding keys, allowing unrestricted use of the key on the remote host. The client now serializes all constraint extensions. Additionally, the in-memory keyring returned by NewKeyring() now rejects keys with unsupported constraint extensions instead of silently ignoring them.

The in-memory keyring returned by NewKeyring() silently accepted keys with the ConfirmBeforeUse constraint but never enforced it. The key would sign without any confirmation prompt, with no indication to the caller that the constraint was not in effect. NewKeyring() now returns an error when unsupported constraints are requested.

For certain crafted inputs, a 'ed25519.PrivateKey' was created by casting malformed wire bytes, leading to a panic when used.

SSH Agent servers do not validate the size of messages when processing new identity requests, which may cause the program to panic if the message is malformed due to an out of bounds read.

SSH servers parsing GSSAPI authentication requests do not validate the number of mechanisms specified in the request, allowing an attacker to cause unbounded memory consumption.

Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection.

Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking.

Previously, a channel registered in the mux's chanList is not usable until it is established. A malicious peer was able flood the channel's incomingRequests, deadlocking the entire connection.

Now, we add an atomic established state, set when a channel becomes usable. Until such a time, handlePacket drops every packet other than the open confirmation/failure, without blocking and without tearing down the connection.

The source-address critical option in the Permissions returned by an authentication callback was only enforced for the PublicKeyCallback and VerifiedPublicKeyCallback paths, extending the fix for CVE-2026-46595. Permissions returned by the PasswordCallback, KeyboardInteractiveCallback, NoClientAuthCallback, and GSSAPIWithMICConfig.AllowLogin callbacks were not validated against the client's remote address, so a source-address restriction set by those callbacks was silently ignored. The check is now applied to the Permissions returned by any authentication callback.

The golang.org/x/crypto/openpgp package is unsafe by design, has numerous known security issues, is not maintained, and should not be used.

If you are required to interoperate with OpenPGP systems and need a maintained package, consider github.com/ProtonMail/go-crypto/openpgp which is a maintained fork that aims to be a drop-in replacement for this package.

Previously, CVE-2024-45337 fixed an authorization bypass for misused ssh server configurations; if any other type of callback is passed other than public key, then the source-address validation would be skipped.

Previously, a revoked 'SignatureKey' belonging to a CA was not correctly checked for revocation. Now, both the 'key' and 'key.SignatureKey' are checked for @revoked.

When writing data larger than 4GB in a single Write call on an SSH channel, an integer overflow in the internal payload size calculation caused the write loop to spin indefinitely, sending empty packets without making progress. The size comparison now uses int64 to prevent truncation.

The Verify() method for FIDO/U2F security key types (sk-ecdsa-sha2-nistp256@openssh.com, sk-ssh-ed25519@openssh.com) did not check the User Presence flag. Signatures generated without physical touch were accepted, allowing unattended use of a hardware security key. To restore the previous behavior, return a "no-touch-required" extension in Permissions.Extensions from PublicKeyCallback.

The RSA and DSA public key parsers did not enforce size limits on key parameters. A crafted public key with an excessively large modulus or DSA parameter could cause several minutes of CPU consumption during signature verification. This could be triggered by unauthenticated clients during public key authentication. RSA moduli are now limited to 8192 bits, and DSA parameters are validated per FIPS 186-2.

A malicious SSH peer could send unsolicited global request responses to fill an internal buffer, blocking the connection's read loop. The blocked goroutine could not be released by calling Close(), resulting in a resource leak per connection. Unsolicited global responses are now discarded.

An authenticated SSH client that repeatedly opened channels which were rejected by the server caused unbounded memory growth, eventually crashing the server process and affecting all connected users. Rejected channels are now properly removed from the connection's internal state and released for garbage collection.