MEDIUM · 5.5

CVE-2026-45983

In the Linux kernel, the following vulnerability has been resolved: nfsd: never defer requests during idmap lookup During v4 request compound arg decoding, some ops (e.g. SETATTR) can trigger idmap ...

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: nfsd: never defer requests during idmap lookup During v4 request compound arg decoding, some ops (e.g. SETATTR) can trigger idmap lookup upcalls. When those upcall responses get delayed beyond the allowed time limit, cache_check() will mark the request for deferral and cause it to be dropped. This prevents nfs4svc_encode_compoundres from being executed, and thus the session slot flag NFSD4_SLOT_INUSE never gets cleared. Subsequent client requests will fail with NFSERR_JUKEBOX, given that the slot will be marked as in-use, making the SEQUENCE op fail. Fix this by making sure that the RQ_USEDEFERRAL flag is always clear during nfs4svc_decode_compoundargs(), since no v4 request should ever be deferred.

CVSS Score

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH

Affected Products

VendorProductVersions
LinuxLinux Kernel>= 2.6.30, < 5.10.252

References

FAQ

What is CVE-2026-45983?

CVE-2026-45983 is a vulnerability with a CVSS score of 5.5 (MEDIUM). In the Linux kernel, the following vulnerability has been resolved: nfsd: never defer requests during idmap lookup During v4 request compound arg decoding, some ops (e.g. SETATTR) can trigger idmap ...

How severe is CVE-2026-45983?

CVE-2026-45983 has been rated MEDIUM with a CVSS base score of 5.5/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-45983?

Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel.