Answer in brief
CVE-2026-89656 records a Critical severity (CVSS 9.8) vulnerability in libceph: reject buckets with mismatched CRUSH ids. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 9.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=66a0e2d579dbec5c676cfe446234ffebb267c564 <3516a4131c4e45d62ee4e42e82c36930e8c1fbbd || >=66a0e2d579dbec5c676cfe446234ffebb267c564 <00562ccd4e88d092b9b851df50fad20442bfeb24 || >=66a0e2d579dbec5c676cfe446234ffebb267c564 <79900d978158b2d80eef952fc41b9e4dc58d7b83 || >=66a0e2d579dbec5c676cfe446234ffebb267c564 <3cde4a8302301679937474a5f7a851394cc1bd11 | 3516a4131c4e45d62ee4e42e82c36930e8c1fbbd, 00562ccd4e88d092b9b851df50fad20442bfeb24, 79900d978158b2d80eef952fc41b9e4dc58d7b83, 3cde4a8302301679937474a5f7a851394cc1bd11 |
| Linux/Linuxgeneric | 4.11 | Not reported |
| Linux/Linuxgeneric | >=66a0e2d579dbec5c676cfe446234ffebb267c564 <ee59040d6ed1a5f8d10d27174b8f32c90ca8e89a || >=66a0e2d579dbec5c676cfe446234ffebb267c564 <baad5875fdd2f5e248250fc3519bb045d64f1716 || >=66a0e2d579dbec5c676cfe446234ffebb267c564 <4aeb93daadf388e72073abc204312dd364eeb30a || >=66a0e2d579dbec5c676cfe446234ffebb267c564 <6e5c6ce252b1eccfd41670a5cf95ab44f7ba7022 || >=66a0e2d579dbec5c676cfe446234ffebb267c564 <3516a4131c4e45d62ee4e42e82c36930e8c1fbbd || >=66a0e2d579dbec5c676cfe446234ffebb267c564 <00562ccd4e88d092b9b851df50fad20442bfeb24 || >=66a0e2d579dbec5c676cfe446234ffebb267c564 <79900d978158b2d80eef952fc41b9e4dc58d7b83 || >=66a0e2d579dbec5c676cfe446234ffebb267c564 <3cde4a8302301679937474a5f7a851394cc1bd11 | ee59040d6ed1a5f8d10d27174b8f32c90ca8e89a, baad5875fdd2f5e248250fc3519bb045d64f1716, 4aeb93daadf388e72073abc204312dd364eeb30a, 6e5c6ce252b1eccfd41670a5cf95ab44f7ba7022, 3516a4131c4e45d62ee4e42e82c36930e8c1fbbd, 00562ccd4e88d092b9b851df50fad20442bfeb24, 79900d978158b2d80eef952fc41b9e4dc58d7b83, 3cde4a8302301679937474a5f7a851394cc1bd11 |
Published upstream
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 19, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 11, 2026
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.
Quoted source text, attributed separately from HOL analysis.