Sicherheitslücken in google-guest-agent

Invoking integer overflow in NewNTUnicodeString in golang.org/x/sys/windows

NewNTUnicodeString does not check for string length overflow. When provided with a string that overflows the maximum size of a NTUnicodeString (a 16-bit number of bytes), it returns a truncated string rather than an error.

Invoking pathological inputs can lead to client panic in golang.org/x/crypto/ssh/agent

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

Invoking VerifiedPublicKeyCallback permissions skip enforcement in golang.org/x/crypto/ssh

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.

• Auf 20250506.01-0ubuntu1.2 aktualisieren

Invoking infinite loop on large channel writes in golang.org/x/crypto/ssh

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.

• Auf 20250506.01-0ubuntu1.2 aktualisieren

Invoking bypass of FIDO/U2F security keys physical interaction in golang.org/x/crypto/ssh

The Verify() method for FIDO/U2F security key types ([email protected], [email protected]) 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.

• Auf 20250506.01-0ubuntu1.2 aktualisieren

Invoking pathological RSA/DSA parameters may cause DoS in golang.org/x/crypto/ssh

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.

Invoking client can cause server deadlock on unexpected responses in golang.org/x/crypto/ssh

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.

• Auf 20250506.01-0ubuntu1.2 aktualisieren

Invoking memory leak when rejecting channels can lead to DoS in golang.org/x/crypto/ssh

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.

Invoking server panic during CheckHostKey/Authenticate in golang.org/x/crypto/ssh

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.

Invoking bypass of certificate restrictions in golang.org/x/crypto/ssh

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.

Invoking byte arithmetic causes underflow and panic in golang.org/x/crypto/ssh

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

Infinite loop in HTTP/2 transport when given bad SETTINGS_MAX_FRAME_SIZE in net/http/internal/http2 in golang.org/x/net

When processing HTTP/2 SETTINGS frames, transport will enter an infinite loop of writing CONTINUATION frames if it receives a SETTINGS_MAX_FRAME_SIZE with a value of 0.

gRPC-Go has an authorization bypass via missing leading slash in :path

gRPC-Go is the Go language implementation of gRPC. Versions prior to 1.79.3 have an authorization bypass resulting from improper input validation of the HTTP/2 `:path` pseudo-header. The gRPC-Go server was too lenient in its routing logic, accepting requests where the `:path` omitted the mandatory leading slash (e.g., `Service/Method` instead of `/Service/Method`). While the server successfully routed these requests to the correct handler, authorization interceptors (including the official `grpc/authz` package) evaluated the raw, non-canonical path string. Consequently, "deny" rules defined using canonical paths (starting with `/`) failed to

Unbounded memory consumption in golang.org/x/crypto/ssh

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.

• Auf 20250506.01-0ubuntu1.1 aktualisieren