High severity · published Sep 11, 2026
CVE-2026-89699
nfsd: validate symlink target length in NFSv4 CREATE
7.5
CVSS
0.5%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 43% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
Linux · Linux
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 before 36011308b3f01ce7dc9954f3cefcbb5291af9f95; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 before 888dad4b557352cf85be31613407b5ba51ad07d1; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 before 8661d3cb38fd148947e57dbc0871fd4d3fa33bbf; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 before 3ef5e7a01a4d74995a65496bc9166d1e980a4355; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 before b24843ea3de1676b29902457b38507c95a80649b; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 before 895a485cd3758031ef9993c0d53cf19ce8fb4ccc; +3 more · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-89699
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-89699
git.kernel.org
https://git.kernel.org/stable/c/041f57056e5fb9c80adc088269322d2c61074406
git.kernel.org
https://git.kernel.org/stable/c/36011308b3f01ce7dc9954f3cefcbb5291af9f95
git.kernel.org
https://git.kernel.org/stable/c/3ef5e7a01a4d74995a65496bc9166d1e980a4355
git.kernel.org
https://git.kernel.org/stable/c/45ec115cbfecb4b3cfab7fca6f73d1b60696a25a
git.kernel.org
https://git.kernel.org/stable/c/8661d3cb38fd148947e57dbc0871fd4d3fa33bbf
git.kernel.org
https://git.kernel.org/stable/c/888dad4b557352cf85be31613407b5ba51ad07d1
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