The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - nfsd: fix heap overflow in NFSv4.0 LOCK replay cache The NFSv4.0 replay cache uses a fixed 112-byte inline     buffer (rp_ibuf[NFSD4_REPLAY_ISIZE]) to store encoded operation responses. This size was calculated based     on OPEN responses and does not account for LOCK denied responses, which include the conflicting lock owner     as a variable-length field up to 1024 bytes (NFS4_OPAQUE_LIMIT). When a LOCK operation is denied due to a     conflict with an existing lock that has a large owner, nfsd4_encode_operation() copies the full encoded     response into the undersized replay buffer via read_bytes_from_xdr_buf() with no bounds check. This     results in a slab-out-of-bounds write of up to 944 bytes past the end of the buffer, corrupting adjacent     heap memory. This can be triggered remotely by an unauthenticated attacker with two cooperating NFSv4.0     clients: one sets a lock with a large owner string, then the other requests a conflicting lock to provoke     the denial. We could fix this by increasing NFSD4_REPLAY_ISIZE to allow for a full opaque, but that would     increase the size of every stateowner, when most lockowners are not that large. Instead, fix this by     checking the encoded response length against NFSD4_REPLAY_ISIZE before copying into the replay buffer. If     the response is too large, set rp_buflen to 0 to skip caching the replay payload. The status is still     cached, and the client already received the correct response on the original request. (CVE-2026-31402)

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Linux Distros Unpatched Vulnerability : CVE-2026-31402

high Nessus Plugin ID 304931

Version 1.2