nfsd: validate symlink target length in NFSv4 CREATE (CVE-2026-89699) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-89699

nfsd: validate symlink target length in NFSv4 CREATE

Answer in brief

CVE-2026-89699 records a Unknown severity vulnerability in nfsd: validate symlink target length in NFSv4 CREATE. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 11, 2026Updated Sep 11, 2026Source checked Sep 11, 2026First seen by HOL Sep 11, 2026Material review Sep 11, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Linux/Linuxgeneric	>=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <b24843ea3de1676b29902457b38507c95a80649b \|\| >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <895a485cd3758031ef9993c0d53cf19ce8fb4ccc \|\| >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <45ec115cbfecb4b3cfab7fca6f73d1b60696a25a \|\| >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <041f57056e5fb9c80adc088269322d2c61074406	b24843ea3de1676b29902457b38507c95a80649b, 895a485cd3758031ef9993c0d53cf19ce8fb4ccc, 45ec115cbfecb4b3cfab7fca6f73d1b60696a25a, 041f57056e5fb9c80adc088269322d2c61074406
Linux/Linuxgeneric	2.6.12	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to b24843ea3de1676b29902457b38507c95a80649b if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 11, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: nfsd: validate symlink target length in NFSv4 CREATE nfsd4_decode_create() accepts an unbounded cr_datalen from the wire for NF4LNK symlink targets, allowing a client to force a kmalloc of up to the maximum RPC payload size (several MiB) per COMPOUND op that persists until compound teardown. The VFS rejects oversized targets with ENAMETOOLONG, but the allocation has already occurred. Reject cr_datalen == 0 early with nfserr_inval and cr_datalen greater than NFS4_MAXPATHLEN (PATH_MAX) with nfserr_nametoolong to bound the allocation.

Quoted source text, attributed separately from HOL analysis.