- 9.8CriticalCVSS base score
- 0.51%Exploitation in 30 daysEPSS · top 56% 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: libceph: reject buckets with mismatched CRUSH ids crush_decode() stores bucket data by array slot, and the mapper later derives the per-bucket workspace index from the decoded bucket id. A malformed map can therefore make one bucket reuse another bucket's workspace by encoding an id different from -1 - slot. For uniform buckets, the second replica selection expands the source bucket's permutation into that aliased workspace buffer. If the source bucket is larger than the aliased bucket, the write runs past the smaller permutation array and can escape the kvmalloc'd CRUSH workspace. KASAN reports a slab OOB write of 4 bytes in bucket_perm_choose(). Reject buckets whose encoded id does not match their array slot. Valid CRUSH maps already use the canonical negative id corresponding to the bucket slot, so this restores the invariant expected by work->work[-1 - in->id] without changing valid map behavior.
Timeline
ID reserved
By Linux
Published
- 38 days later
· 38 days 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 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Received | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.51% · top 56% of all CVEs (11 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Affected products
- affected 66a0e2d579dbec5c676cfe446234ffebb267c564 – < ee59040d6ed1a5f8d10d27174b8f32c90ca8e89a
- affected 66a0e2d579dbec5c676cfe446234ffebb267c564 – < baad5875fdd2f5e248250fc3519bb045d64f1716
- affected 66a0e2d579dbec5c676cfe446234ffebb267c564 – < 4aeb93daadf388e72073abc204312dd364eeb30a
- affected 66a0e2d579dbec5c676cfe446234ffebb267c564 – < 6e5c6ce252b1eccfd41670a5cf95ab44f7ba7022
- affected 66a0e2d579dbec5c676cfe446234ffebb267c564 – < 3516a4131c4e45d62ee4e42e82c36930e8c1fbbd
- affected 66a0e2d579dbec5c676cfe446234ffebb267c564 – < 00562ccd4e88d092b9b851df50fad20442bfeb24
- affected 66a0e2d579dbec5c676cfe446234ffebb267c564 – < 79900d978158b2d80eef952fc41b9e4dc58d7b83
- affected 66a0e2d579dbec5c676cfe446234ffebb267c564 – < 3cde4a8302301679937474a5f7a851394cc1bd11
- affected 4.11
- unaffected < 4.11
- unaffected 5.10.270 – ≤ 5.10.*
- unaffected 5.15.221 – ≤ 5.15.*
- unaffected 6.1.188 – ≤ 6.1.*
- unaffected 6.6.157 – ≤ 6.6.*
- unaffected 6.12.109 – ≤ 6.12.*
- unaffected 6.18.50 – ≤ 6.18.*
- unaffected 7.2.4 – ≤ 7.2.*
- unaffected 7.3 – ≤ *
References
References8
- https://git.kernel.org/stable/c/ee59040d6ed1a5f8d10d27174b8f32c90ca8e89a (opens in a new tab)
- https://git.kernel.org/stable/c/baad5875fdd2f5e248250fc3519bb045d64f1716 (opens in a new tab)
- https://git.kernel.org/stable/c/4aeb93daadf388e72073abc204312dd364eeb30a (opens in a new tab)
- https://git.kernel.org/stable/c/6e5c6ce252b1eccfd41670a5cf95ab44f7ba7022 (opens in a new tab)
- https://git.kernel.org/stable/c/3516a4131c4e45d62ee4e42e82c36930e8c1fbbd (opens in a new tab)
- https://git.kernel.org/stable/c/00562ccd4e88d092b9b851df50fad20442bfeb24 (opens in a new tab)
- https://git.kernel.org/stable/c/79900d978158b2d80eef952fc41b9e4dc58d7b83 (opens in a new tab)
- https://git.kernel.org/stable/c/3cde4a8302301679937474a5f7a851394cc1bd11 (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-2026-76568 (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-2026-89656)Record last updated .