CVE-2025-21691cachestat: fix page cache statistics permission checking
- 5.5MediumCVSS base score
- 0.20%Exploitation in 30 daysEPSS · top 89% 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: cachestat: fix page cache statistics permission checking When the 'cachestat()' system call was added in commit cf264e1329fb ("cachestat: implement cachestat syscall"), it was meant to be a much more convenient (and performant) version of mincore() that didn't need mapping things into the user virtual address space in order to work. But it ended up missing the "check for writability or ownership" fix for mincore(), done in commit 134fca9063ad ("mm/mincore.c: make mincore() more conservative"). This just adds equivalent logic to 'cachestat()', modified for the file context (rather than vma).
Timeline
ID reserved
By Linux
- 43 days later
· 43 days later
Published
- 15 months later
· 15 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 |
|---|---|---|---|
| NVDNVD · Analyzed | 3.1 | Medium5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.20% · top 89% of all CVEs (13 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.5.
Affected products
- affected cf264e1329fb0307e044f7675849f9f38b44c11a – < 7d6405c13b0d8a8367cd8df63f118b619a3f0dd2
- affected cf264e1329fb0307e044f7675849f9f38b44c11a – < 780ab8329672464984cf1344bd5c3993af0226c7
- affected cf264e1329fb0307e044f7675849f9f38b44c11a – < 97153a05077f618f7471f50a78158602badccb30
- affected cf264e1329fb0307e044f7675849f9f38b44c11a – < 5f537664e705b0bf8b7e329861f20128534f6a83
- affected 6.5
- unaffected < 6.5
- unaffected 6.6.75 – ≤ 6.6.*
- unaffected 6.12.12 – ≤ 6.12.*
- unaffected 6.13.1 – ≤ 6.13.*
- unaffected 6.14 – ≤ *
References
References4
- https://git.kernel.org/stable/c/7d6405c13b0d8a8367cd8df63f118b619a3f0dd2 (opens in a new tab)
- https://git.kernel.org/stable/c/780ab8329672464984cf1344bd5c3993af0226c7 (opens in a new tab)
- https://git.kernel.org/stable/c/97153a05077f618f7471f50a78158602badccb30 (opens in a new tab)
- https://git.kernel.org/stable/c/5f537664e705b0bf8b7e329861f20128534f6a83 (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-2025-2640 (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-2025-21691)Record last updated .