# ipv6: seg6: clear IPv4 control block on IPIP decapsulation

CVE record · `CVE-2026-80840`

- **Identifiers:** `CVE-2026-80840`
- **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: `891ef8dd2a8d14e4e73a81dcdb135b574c57f556 to before 10fd1a8f58ac619a9e251f2858e2e2c8fd6cd667` (git)
  - affected: `891ef8dd2a8d14e4e73a81dcdb135b574c57f556 to before eb0f422487228e140f3d609b032ac61aedcab8fa` (git)
  - affected: `891ef8dd2a8d14e4e73a81dcdb135b574c57f556 to before 9039e4f3e1c0ffe2b575b655b3f58fdd10f7e40c` (git)
  - affected: `891ef8dd2a8d14e4e73a81dcdb135b574c57f556 to before f52f1e75716d2ee49e013edf204ac92337c72fd8` (git)
  - affected: `891ef8dd2a8d14e4e73a81dcdb135b574c57f556 to before 0e3f01fe2e704e76af4385b8a1742641885a191c` (git)
  - affected: `891ef8dd2a8d14e4e73a81dcdb135b574c57f556 to before 3e4476e58343fb8f2fffced9e22d935376b17aaf` (git)
  - affected: `891ef8dd2a8d14e4e73a81dcdb135b574c57f556 to before bf1c1151560d11036a144d917fa4c131831342d7` (git)
  - affected: `891ef8dd2a8d14e4e73a81dcdb135b574c57f556 to before f4be3b391265e24c7720fc867c50062b436acf33` (git)
  - affected: `891ef8dd2a8d14e4e73a81dcdb135b574c57f556 to before 44930446dde45a7a90fe1446fa38eb0e2c561646` (git)
  - Other versions: unaffected
- Vendor: Linux. Product: Linux.
  - affected: `4.14`
  - unaffected: `before 4.14` (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:** 0.0021, the 10th 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-2026-80840](https://www.cve.org/CVERecord?id=CVE-2026-80840)
- [NVD: CVE-2026-80840](https://nvd.nist.gov/vuln/detail/CVE-2026-80840)

### References from the CNA

- <https://git.kernel.org/stable/c/10fd1a8f58ac619a9e251f2858e2e2c8fd6cd667>
- <https://git.kernel.org/stable/c/eb0f422487228e140f3d609b032ac61aedcab8fa>
- <https://git.kernel.org/stable/c/9039e4f3e1c0ffe2b575b655b3f58fdd10f7e40c>
- <https://git.kernel.org/stable/c/f52f1e75716d2ee49e013edf204ac92337c72fd8>
- <https://git.kernel.org/stable/c/0e3f01fe2e704e76af4385b8a1742641885a191c>
- <https://git.kernel.org/stable/c/3e4476e58343fb8f2fffced9e22d935376b17aaf>
- <https://git.kernel.org/stable/c/bf1c1151560d11036a144d917fa4c131831342d7>
- <https://git.kernel.org/stable/c/f4be3b391265e24c7720fc867c50062b436acf33>
- <https://git.kernel.org/stable/c/44930446dde45a7a90fe1446fa38eb0e2c561646>

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-2026-80840>
- Everything that needs attention now: <https://agentprime.io/advisories/critical.md>

---

The web page: <https://agentprime.io/advisories/CVE-2026-80840/>. Everything for agents: <https://agentprime.io/llms.txt>.