CVE-2026-45983
What it is
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.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of service disruption.
- Exploit odds
- 0.1% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.1% in the next 30 days (EPSS).
- Severity: 5.5 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.1% · EPSS, next 30 days
- Record status
- Analyzed
Affected
- Linux Kernel < 5.10.252
- Linux Kernel < 5.15.202
- Linux Kernel < 6.1.165
- Linux Kernel < 6.6.128
- Linux Kernel < 6.12.75
- Linux Kernel < 6.18.14
- Linux Kernel < 6.19.4
Attack profile CVSS 3.1 · 5.5
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-45983.md and follow it. Check whether this project is affected by CVE-2026-45983. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/063a6f22478ef929625000a2caf54667725c1dfd
- https://git.kernel.org/stable/c/243f71ed873ff3feeb6f9b5cb145d63f7188b4c4
- https://git.kernel.org/stable/c/3a72c7dedc99b321e0f267e4e999e5baf07c4593
- https://git.kernel.org/stable/c/8dff54fe88c0dcd4c55bff9fc2fa6ca968290826
- https://git.kernel.org/stable/c/99e17b20fddac19a228d213e00f6b9e1c10daff9
- https://git.kernel.org/stable/c/b9abb760db20504240a7147f27934d900cd80b23
- https://git.kernel.org/stable/c/d75ec4504a4340b033b15cad0303988b3089dd93
- https://git.kernel.org/stable/c/f9c206cdc4266caad6a9a7f46341420a10f03ccb
References
- https://git.kernel.org/stable/c/063a6f22478ef929625000a2caf54667725c1dfd
- https://git.kernel.org/stable/c/243f71ed873ff3feeb6f9b5cb145d63f7188b4c4
- https://git.kernel.org/stable/c/3a72c7dedc99b321e0f267e4e999e5baf07c4593
- https://git.kernel.org/stable/c/8dff54fe88c0dcd4c55bff9fc2fa6ca968290826
- https://git.kernel.org/stable/c/99e17b20fddac19a228d213e00f6b9e1c10daff9
- https://git.kernel.org/stable/c/b9abb760db20504240a7147f27934d900cd80b23
- https://git.kernel.org/stable/c/d75ec4504a4340b033b15cad0303988b3089dd93
- https://git.kernel.org/stable/c/f9c206cdc4266caad6a9a7f46341420a10f03ccb