Bug 2532157 (CVE-2026-89699) - CVE-2026-89699 kernel: Linux kernel: nfsd vulnerable to denial of service via oversized NFSv4 symlink targets
Summary: CVE-2026-89699 kernel: Linux kernel: nfsd vulnerable to denial of service via...
Keywords:
Status: NEW
Alias: CVE-2026-89699
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Product Security DevOps Team
QA Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-09-11 21:01 UTC by OSIDB Bzimport
Modified: 2026-09-11 21:25 UTC (History)
15 users (show)

Fixed In Version:
Clone Of:
Environment:
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Description OSIDB Bzimport 2026-09-11 21:01:31 UTC
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.


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