# xfrm: fix xfrm_state_construct() auth-trunc leak

CVE record · `CVE-2026-80843`

- **Identifiers:** `CVE-2026-80843`
- **State:** Confirmed
- **Severity:** No CVSS score
- **Critical:** No
- **CNA:** Linux
- **Technologies:** [Linux kernel](https://agentprime.io/advisories/technology/linux-kernel.md)
- **Published:** 4 Sept 2026
- **Updated:** 19 Oct 2026
- **Reviewed by a person:** No

Published by the CVE Program (CNA: Linux) at 4 Sept 2026, 15:54 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.

## Affected products, as the CNA wrote them

- Vendor: Linux. Product: Linux.
  - affected: `4447bb33f09444920a8f1d89e1540137429351b6 to before 958ae9f261319e1cdc44879886bcda2263258cca` (git)
  - affected: `4447bb33f09444920a8f1d89e1540137429351b6 to before fb7f3e74789a3c89647f4eb768f6dfaf4a751e72` (git)
  - affected: `4447bb33f09444920a8f1d89e1540137429351b6 to before ba0c110c205855b3f1e3130d8c0fdb484d704c8c` (git)
  - affected: `4447bb33f09444920a8f1d89e1540137429351b6 to before c8837bbe792257af547fd1c0252553ce13148795` (git)
  - affected: `4447bb33f09444920a8f1d89e1540137429351b6 to before 71d42da01740ec6557837bebec0bc48cfc3b4c39` (git)
  - affected: `4447bb33f09444920a8f1d89e1540137429351b6 to before cf67361e78dca488d6e4df8396a53e6745a3a80e` (git)
  - affected: `4447bb33f09444920a8f1d89e1540137429351b6 to before 37426395cb90ef217beec8407a14bd82153793d3` (git)
  - affected: `4447bb33f09444920a8f1d89e1540137429351b6 to before be19d20e53a239572bb2a28efcc1cd2b069b1ef9` (git)
  - affected: `4447bb33f09444920a8f1d89e1540137429351b6 to before c12cbf56320fb633484ee0ca1fb7d68d6b64b213` (git)
  - Other versions: unaffected
- Vendor: Linux. Product: Linux.
  - affected: `2.6.33`
  - unaffected: `before 2.6.33` (semver)
  - unaffected: `5.10.269 to 5.10.*, inclusive` (semver)
  - unaffected: `5.15.220 to 5.15.*, inclusive` (semver)
  - unaffected: `6.1.187 to 6.1.*, inclusive` (semver)
  - unaffected: `6.6.156 to 6.6.*, inclusive` (semver)
  - unaffected: `6.12.108 to 6.12.*, inclusive` (semver)
  - unaffected: `6.18.49 to 6.18.*, inclusive` (semver)
  - unaffected: `7.1.13 to 7.1.*, inclusive` (semver)
  - unaffected: `7.2.3 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

No source has published a CVSS score for this record yet.

- **CISA KEV:** Not listed.
- **EPSS:** 0.0019, the 9th 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 4 Sept 2026. New records show when each source confirmed them.

## Sources

- [CVE List: CVE-2026-80843](https://www.cve.org/CVERecord?id=CVE-2026-80843)
- [NVD: CVE-2026-80843](https://nvd.nist.gov/vuln/detail/CVE-2026-80843)

### References from the CNA

- <https://git.kernel.org/stable/c/958ae9f261319e1cdc44879886bcda2263258cca>
- <https://git.kernel.org/stable/c/fb7f3e74789a3c89647f4eb768f6dfaf4a751e72>
- <https://git.kernel.org/stable/c/ba0c110c205855b3f1e3130d8c0fdb484d704c8c>
- <https://git.kernel.org/stable/c/c8837bbe792257af547fd1c0252553ce13148795>
- <https://git.kernel.org/stable/c/71d42da01740ec6557837bebec0bc48cfc3b4c39>
- <https://git.kernel.org/stable/c/cf67361e78dca488d6e4df8396a53e6745a3a80e>
- <https://git.kernel.org/stable/c/37426395cb90ef217beec8407a14bd82153793d3>
- <https://git.kernel.org/stable/c/be19d20e53a239572bb2a28efcc1cd2b069b1ef9>
- <https://git.kernel.org/stable/c/c12cbf56320fb633484ee0ca1fb7d68d6b64b213>

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-2026-80843>
- Everything that needs attention now: <https://agentprime.io/advisories/critical.md>

---

The web page: <https://agentprime.io/advisories/CVE-2026-80843/>. Everything for agents: <https://agentprime.io/llms.txt>.