# ip6_gre: fix hardware header length for NBMA tunnels

CVE record · `CVE-2026-89562`

- **Identifiers:** `CVE-2026-89562`
- **State:** Confirmed
- **Severity:** CVSS 7.8 High
- **Critical:** No
- **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, 19:44 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: `832ba596494b2c9eac7760259eff2d8b7dcad0ee to before cb1afd087aedc90e5274537e4fb9bf3f98e5afdb` (git)
  - affected: `832ba596494b2c9eac7760259eff2d8b7dcad0ee to before 7719f6e7ed2ffddc2c3bb61f4467b76d49e0af6a` (git)
  - affected: `832ba596494b2c9eac7760259eff2d8b7dcad0ee to before b1e95e3602d8e112458627f14c6c31c21f2188cb` (git)
  - affected: `832ba596494b2c9eac7760259eff2d8b7dcad0ee to before c3457a5aae5fb43f7023d3f3dc472c2afa22acf0` (git)
  - affected: `832ba596494b2c9eac7760259eff2d8b7dcad0ee to before 8bfe746afee38dd6e4348ddcd22d554789dbb9ff` (git)
  - affected: `832ba596494b2c9eac7760259eff2d8b7dcad0ee to before b8282668d8fa7c61b80e8e4890729031c291a16c` (git)
  - affected: `832ba596494b2c9eac7760259eff2d8b7dcad0ee to before 565038b0092f65afe384961c0f548d605bf438b9` (git)
  - affected: `832ba596494b2c9eac7760259eff2d8b7dcad0ee to before 505b6d296c486ef7d1274f279d4c43a172f63224` (git)
  - affected: `cf3d9717a5271573fa193c4dfa0df856295d5b15` (git)
  - affected: `187a6daf5db45adc807c85bbe285319107bed198` (git)
  - affected: `d9897bb66ce989325b4bf4cdbb6a799e4ac878b6` (git)
  - affected: `4.19.162 to before 4.20` (semver)
  - and 2 more
  - Other versions: unaffected
- Vendor: Linux. Product: Linux.
  - affected: `5.10`
  - unaffected: `before 5.10` (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

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

- **CISA KEV:** Not listed.
- **EPSS:** 0.0013, the 2nd 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-2026-89562](https://www.cve.org/CVERecord?id=CVE-2026-89562)
- [NVD: CVE-2026-89562](https://nvd.nist.gov/vuln/detail/CVE-2026-89562)

### References from the CNA

- <https://git.kernel.org/stable/c/cb1afd087aedc90e5274537e4fb9bf3f98e5afdb>
- <https://git.kernel.org/stable/c/7719f6e7ed2ffddc2c3bb61f4467b76d49e0af6a>
- <https://git.kernel.org/stable/c/b1e95e3602d8e112458627f14c6c31c21f2188cb>
- <https://git.kernel.org/stable/c/c3457a5aae5fb43f7023d3f3dc472c2afa22acf0>
- <https://git.kernel.org/stable/c/8bfe746afee38dd6e4348ddcd22d554789dbb9ff>
- <https://git.kernel.org/stable/c/b8282668d8fa7c61b80e8e4890729031c291a16c>
- <https://git.kernel.org/stable/c/565038b0092f65afe384961c0f548d605bf438b9>
- <https://git.kernel.org/stable/c/505b6d296c486ef7d1274f279d4c43a172f63224>

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-2026-89562>
- Everything that needs attention now: <https://agentprime.io/advisories/critical.md>

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The web page: <https://agentprime.io/advisories/CVE-2026-89562/>. Everything for agents: <https://agentprime.io/llms.txt>.