# xfrm6: fix out-of-bounds write in xfrm6_input_addr() when secpath is full

CVE record · `CVE-2026-89783`

- **Identifiers:** `CVE-2026-89783`
- **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:** 16 Sept 2026
- **Updated:** 19 Oct 2026
- **Reviewed by a person:** No

Published by the CVE Program (CNA: Linux) at 16 Sept 2026, 08:48 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: `9473e1f631de339c50bde1e3bd09e1045fe90fd5 to before 91fc387f63c00ddfb5221127a17bac97549a8343` (git)
  - affected: `9473e1f631de339c50bde1e3bd09e1045fe90fd5 to before 68e8737fe8e72f085c608cff322b3d2de8340af1` (git)
  - affected: `9473e1f631de339c50bde1e3bd09e1045fe90fd5 to before 8fe2c53fb81f5ad5be43af2ad09583f7c78b4b77` (git)
  - affected: `9473e1f631de339c50bde1e3bd09e1045fe90fd5 to before bdcda866c89f9a8b1acdabf02d26cde9fbe501d8` (git)
  - affected: `9473e1f631de339c50bde1e3bd09e1045fe90fd5 to before 48996649222e95008cdb98cd58579e3fc8e5ee06` (git)
  - affected: `9473e1f631de339c50bde1e3bd09e1045fe90fd5 to before 0f679e0523ddfff3fb554336ceb874b0e51e9cd3` (git)
  - affected: `9473e1f631de339c50bde1e3bd09e1045fe90fd5 to before 5f35a29a5eed3d80befd32050843ac88dea3d61a` (git)
  - affected: `9473e1f631de339c50bde1e3bd09e1045fe90fd5 to before 5d9e3bf34fec9a5d237e4b7cef4a707bc2e091bc` (git)
  - Other versions: unaffected
- Vendor: Linux. Product: Linux.
  - affected: `2.6.25`
  - unaffected: `before 2.6.25` (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: `6.12.110 to 6.12.*, inclusive` (semver)
  - unaffected: `6.18.52 to 6.18.*, inclusive` (semver)
  - unaffected: `7.2.6 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:** 0.0071, the 54th 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 16 Sept 2026. New records show when each source confirmed them.

## Sources

- [CVE List: CVE-2026-89783](https://www.cve.org/CVERecord?id=CVE-2026-89783)
- [NVD: CVE-2026-89783](https://nvd.nist.gov/vuln/detail/CVE-2026-89783)

### References from the CNA

- <https://git.kernel.org/stable/c/91fc387f63c00ddfb5221127a17bac97549a8343>
- <https://git.kernel.org/stable/c/68e8737fe8e72f085c608cff322b3d2de8340af1>
- <https://git.kernel.org/stable/c/8fe2c53fb81f5ad5be43af2ad09583f7c78b4b77>
- <https://git.kernel.org/stable/c/bdcda866c89f9a8b1acdabf02d26cde9fbe501d8>
- <https://git.kernel.org/stable/c/48996649222e95008cdb98cd58579e3fc8e5ee06>
- <https://git.kernel.org/stable/c/0f679e0523ddfff3fb554336ceb874b0e51e9cd3>
- <https://git.kernel.org/stable/c/5f35a29a5eed3d80befd32050843ac88dea3d61a>
- <https://git.kernel.org/stable/c/5d9e3bf34fec9a5d237e4b7cef4a707bc2e091bc>

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-2026-89783>
- Everything that needs attention now: <https://agentprime.io/advisories/critical.md>

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The web page: <https://agentprime.io/advisories/CVE-2026-89783/>. Everything for agents: <https://agentprime.io/llms.txt>.