# libceph: reject buckets with mismatched CRUSH ids

CVE record · `CVE-2026-89656`

- **Identifiers:** `CVE-2026-89656`
- **State:** Confirmed
- **Severity:** CVSS 9.8 Critical
- **Critical:** Yes: CVSS 9+
- **CNA:** Linux
- **Technologies:** [Linux kernel](https://agentprime.io/advisories/technology/linux-kernel.md)
- **Published:** 11 Sept 2026
- **Updated:** 19 Oct 2026
- **Reviewed by a person:** No

Published by the CVE Program (CNA: Linux) at 11 Sept 2026, 19:45 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. This CVE names a vendor and product rather than a package, so the lockfile check doesn’t match it.

## Critical

Critical, because:

- CVSS score 9.8: 9.0 or more.

How we decide what’s critical: <https://agentprime.io/advisories/critical.md>

## Affected products, as the CNA wrote them

- Vendor: Linux. Product: Linux.
  - affected: `66a0e2d579dbec5c676cfe446234ffebb267c564 to before ee59040d6ed1a5f8d10d27174b8f32c90ca8e89a` (git)
  - affected: `66a0e2d579dbec5c676cfe446234ffebb267c564 to before baad5875fdd2f5e248250fc3519bb045d64f1716` (git)
  - affected: `66a0e2d579dbec5c676cfe446234ffebb267c564 to before 4aeb93daadf388e72073abc204312dd364eeb30a` (git)
  - affected: `66a0e2d579dbec5c676cfe446234ffebb267c564 to before 6e5c6ce252b1eccfd41670a5cf95ab44f7ba7022` (git)
  - affected: `66a0e2d579dbec5c676cfe446234ffebb267c564 to before 3516a4131c4e45d62ee4e42e82c36930e8c1fbbd` (git)
  - affected: `66a0e2d579dbec5c676cfe446234ffebb267c564 to before 00562ccd4e88d092b9b851df50fad20442bfeb24` (git)
  - affected: `66a0e2d579dbec5c676cfe446234ffebb267c564 to before 79900d978158b2d80eef952fc41b9e4dc58d7b83` (git)
  - affected: `66a0e2d579dbec5c676cfe446234ffebb267c564 to before 3cde4a8302301679937474a5f7a851394cc1bd11` (git)
  - Other versions: unaffected
- Vendor: Linux. Product: Linux.
  - affected: `4.11`
  - unaffected: `before 4.11` (semver)
  - unaffected: `5.10.270 to 5.10.*, inclusive` (semver)
  - unaffected: `5.15.221 to 5.15.*, inclusive` (semver)
  - unaffected: `6.1.188 to 6.1.*, inclusive` (semver)
  - unaffected: `6.6.157 to 6.6.*, inclusive` (semver)
  - unaffected: `6.12.109 to 6.12.*, inclusive` (semver)
  - unaffected: `6.18.50 to 6.18.*, inclusive` (semver)
  - unaffected: `7.2.4 to 7.2.*, inclusive` (semver)
  - unaffected: `7.3 to *, inclusive` (original_commit_for_fix)
  - Other versions: affected

## Not analysed yet

We haven’t published our own analysis of this CVE. If a person reviews it, this page will say what’s affected and what has to be true for it to matter.

## Severity and exploitation

- 9.8 Critical, CVSS 3.1: `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`, from CNA (Linux)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0051, the 44th percentile, on 14 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

This record came from the full history of the CVE Program, published 11 Sept 2026. New records show when each source confirmed them.

## Sources

- [CVE List: CVE-2026-89656](https://www.cve.org/CVERecord?id=CVE-2026-89656)
- [NVD: CVE-2026-89656](https://nvd.nist.gov/vuln/detail/CVE-2026-89656)

### References from the CNA

- <https://git.kernel.org/stable/c/ee59040d6ed1a5f8d10d27174b8f32c90ca8e89a>
- <https://git.kernel.org/stable/c/baad5875fdd2f5e248250fc3519bb045d64f1716>
- <https://git.kernel.org/stable/c/4aeb93daadf388e72073abc204312dd364eeb30a>
- <https://git.kernel.org/stable/c/6e5c6ce252b1eccfd41670a5cf95ab44f7ba7022>
- <https://git.kernel.org/stable/c/3516a4131c4e45d62ee4e42e82c36930e8c1fbbd>
- <https://git.kernel.org/stable/c/00562ccd4e88d092b9b851df50fad20442bfeb24>
- <https://git.kernel.org/stable/c/79900d978158b2d80eef952fc41b9e4dc58d7b83>
- <https://git.kernel.org/stable/c/3cde4a8302301679937474a5f7a851394cc1bd11>

Facts on this page come from the CVE List as the CNA published them, with CVSS from the sources named above, CISA KEV and FIRST EPSS. Vendors, products and versions are shown as the CNA wrote them. We don’t reproduce the CVE’s description.

## Check whether this affects you

This CVE names a vendor and product rather than a package, so the lockfile check doesn’t match it. Compare the affected versions above with what you run.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), `get_advisory` returns this record and `search_advisories` finds related ones. Setup: <https://agentprime.io/mcp.md>
- As JSON: <https://api.agentprime.io/v1/advisories/CVE-2026-89656>
- Everything that needs attention now: <https://agentprime.io/advisories/critical.md>

---

The web page: <https://agentprime.io/advisories/CVE-2026-89656/>. Everything for agents: <https://agentprime.io/llms.txt>.