# btrfs: fix xattr replace when multiple xattrs are packed in the same item

CVE record · `CVE-2026-98959`

- **Identifiers:** `CVE-2026-98959`
- **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:** 23 Oct 2026
- **Updated:** 24 Oct 2026
- **Reviewed by a person:** No

Published by the CVE Program (CNA: Linux) at 23 Oct 2026, 12:19 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: `5f5bc6b1e2d5a6f827bc860ef2dc5b6f365d1339 to before 7a53bb4668b319fc6c8a3ce2c21635125c7d2712` (git)
  - affected: `5f5bc6b1e2d5a6f827bc860ef2dc5b6f365d1339 to before 5877d7138cc4359d26fd7b010eedfd1b3162348f` (git)
  - affected: `5f5bc6b1e2d5a6f827bc860ef2dc5b6f365d1339 to before a97114b9b00ed3d05156f3b2ddbf797296260389` (git)
  - affected: `5f5bc6b1e2d5a6f827bc860ef2dc5b6f365d1339 to before c1803697a60f22743aa28ad522f805e92d45e3f0` (git)
  - affected: `5f5bc6b1e2d5a6f827bc860ef2dc5b6f365d1339 to before 858bee1c77857aabcc2327cd32dd8266332de332` (git)
  - affected: `43f2e3615d181a7028ab797114c5960977669b2a` (git)
  - affected: `a873146ce4fb025c0b5c1322af5a6bad042f5363` (git)
  - affected: `02590fd855d1690568b2fa439c942e933221b57a` (git)
  - affected: `55e97f654cbbbef70f9714f0e113604dd931e360` (git)
  - affected: `3.10.83 to before 3.11` (semver)
  - affected: `3.12.45 to before 3.13` (semver)
  - affected: `3.14.47 to before 3.15` (semver)
  - and 1 more
  - Other versions: unaffected
- Vendor: Linux. Product: Linux.
  - affected: `3.19`
  - unaffected: `before 3.19` (semver)
  - unaffected: `6.6.160 to 6.6.*, inclusive` (semver)
  - unaffected: `6.12.113 to 6.12.*, inclusive` (semver)
  - unaffected: `6.18.57 to 6.18.*, inclusive` (semver)
  - unaffected: `7.2.11 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:** 0.0061, the 49th percentile, on 6 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 23 Oct 2026. New records show when each source confirmed them.

## Sources

- [CVE List: CVE-2026-98959](https://www.cve.org/CVERecord?id=CVE-2026-98959)
- [NVD: CVE-2026-98959](https://nvd.nist.gov/vuln/detail/CVE-2026-98959)

### References from the CNA

- <https://git.kernel.org/stable/c/7a53bb4668b319fc6c8a3ce2c21635125c7d2712>
- <https://git.kernel.org/stable/c/5877d7138cc4359d26fd7b010eedfd1b3162348f>
- <https://git.kernel.org/stable/c/a97114b9b00ed3d05156f3b2ddbf797296260389>
- <https://git.kernel.org/stable/c/c1803697a60f22743aa28ad522f805e92d45e3f0>
- <https://git.kernel.org/stable/c/858bee1c77857aabcc2327cd32dd8266332de332>

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-2026-98959>
- Everything that needs attention now: <https://agentprime.io/advisories/critical.md>

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The web page: <https://agentprime.io/advisories/CVE-2026-98959/>. Everything for agents: <https://agentprime.io/llms.txt>.