- 7.8HighCVSS base score
- 0.15%Exploitation in 30 daysEPSS · top 96% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: nfsd: provide locking for v4_end_grace Writing to v4_end_grace can race with server shutdown and result in memory being accessed after it was freed - reclaim_str_hashtbl in particularly. We cannot hold nfsd_mutex across the nfsd4_end_grace() call as that is held while client_tracking_op->init() is called and that can wait for an upcall to nfsdcltrack which can write to v4_end_grace, resulting in a deadlock. nfsd4_end_grace() is also called by the landromat work queue and this doesn't require locking as server shutdown will stop the work and wait for it before freeing anything that nfsd4_end_grace() might access. However, we must be sure that writing to v4_end_grace doesn't restart the work item after shutdown has already waited for it. For this we add a new flag protected with nn->client_lock. It is set only while it is safe to make client tracking calls, and v4_end_grace only schedules work while the flag is set with the spinlock held. So this patch adds a nfsd_net field "client_tracking_active" which is set as described. Another field "grace_end_forced", is set when v4_end_grace is written. After this is set, and providing client_tracking_active is set, the laundromat is scheduled. This "grace_end_forced" field bypasses other checks for whether the grace period has finished. This resolves a race which can result in use-after-free.
Timeline
ID reserved
By Linux
- 10 days later
· 10 days later
Published
- 10 months later
· 10 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.15% · top 96% of all CVEs (12 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.
Affected products
- affected 7f5ef2e900d9462bf9cffaf6bb246ed87a20a6d6 – < ca97360860eb02e3ae4ba42c19b439a0fcecbf06
- affected 7f5ef2e900d9462bf9cffaf6bb246ed87a20a6d6 – < e8bfa2401d4c51eca6e48e9b33c798828ca9df61
- affected 7f5ef2e900d9462bf9cffaf6bb246ed87a20a6d6 – < 34eb22836e0cdba093baac66599d68c4cd245a9d
- affected 7f5ef2e900d9462bf9cffaf6bb246ed87a20a6d6 – < 06600719d0f7a723811c45e4d51f5b742f345309
- affected 7f5ef2e900d9462bf9cffaf6bb246ed87a20a6d6 – < ba4811c8b433bfa681729ca42cc62b6034f223b0
- affected 7f5ef2e900d9462bf9cffaf6bb246ed87a20a6d6 – < 53f07d095e7e680c5e4569a55a019f2c0348cdc6
- affected 7f5ef2e900d9462bf9cffaf6bb246ed87a20a6d6 – < 2857bd59feb63fcf40fe4baf55401baea6b4feb4
- affected 3.18
- unaffected < 3.18
- unaffected 5.10.248 – ≤ 5.10.*
- unaffected 5.15.198 – ≤ 5.15.*
- unaffected 6.1.161 – ≤ 6.1.*
- unaffected 6.6.121 – ≤ 6.6.*
- unaffected 6.12.66 – ≤ 6.12.*
- unaffected 6.18.6 – ≤ 6.18.*
- unaffected 6.19 – ≤ *
References
References9
- https://git.kernel.org/stable/c/ca97360860eb02e3ae4ba42c19b439a0fcecbf06 (opens in a new tab)
- https://git.kernel.org/stable/c/e8bfa2401d4c51eca6e48e9b33c798828ca9df61 (opens in a new tab)
- https://git.kernel.org/stable/c/34eb22836e0cdba093baac66599d68c4cd245a9d (opens in a new tab)
- https://git.kernel.org/stable/c/06600719d0f7a723811c45e4d51f5b742f345309 (opens in a new tab)
- https://git.kernel.org/stable/c/ba4811c8b433bfa681729ca42cc62b6034f223b0 (opens in a new tab)
- https://git.kernel.org/stable/c/53f07d095e7e680c5e4569a55a019f2c0348cdc6 (opens in a new tab)
- https://git.kernel.org/stable/c/2857bd59feb63fcf40fe4baf55401baea6b4feb4 (opens in a new tab)
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html (opens in a new tab)
- https://cert-portal.siemens.com/productcert/html/ssa-457936.html (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-4321 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-22980)Record last updated .