# rxrpc: reject undecryptable rxkad response tickets

CVE record · `CVE-2026-31637`

- **Identifiers:** `CVE-2026-31637`
- **State:** Confirmed
- **Severity:** CVSS 9.8 Critical
- **Critical:** Yes: CVSS 9+
- **CNA:** Linux
- **Weakness (CWE):** [CWE-754](https://cwe.mitre.org/data/definitions/754.html)
- **Tags:** [CWE-754](https://agentprime.io/advisories/tag/cwe-754.md)
- **Technologies:** [Linux kernel](https://agentprime.io/advisories/technology/linux-kernel.md)
- **Published:** 24 Apr 2026
- **Updated:** 19 Oct 2026
- **Reviewed by a person:** No

Published by the CVE Program (CNA: Linux) at 24 Apr 2026, 14:44 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.

## 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: `17926a79320afa9b95df6b977b40cca6d8713cea to before 252157d939d179b5d767cb860ff8fa7f8723b67a` (git)
  - affected: `17926a79320afa9b95df6b977b40cca6d8713cea to before a75b3b361dd481d942c5f259a82d59718a41092c` (git)
  - affected: `17926a79320afa9b95df6b977b40cca6d8713cea to before b3a808cd0790b5075aaa2bc3588edf02cd71d352` (git)
  - affected: `17926a79320afa9b95df6b977b40cca6d8713cea to before 47073aab8a3a5a7b41c9bd37d2a3dcbeeccd6c8a` (git)
  - affected: `17926a79320afa9b95df6b977b40cca6d8713cea to before a149dcae23309df9de1c3b6b5d468610ef5ab7de` (git)
  - affected: `17926a79320afa9b95df6b977b40cca6d8713cea to before 22f6258e7b31dba9bf88dce4e3ee7f0f20072e60` (git)
  - affected: `17926a79320afa9b95df6b977b40cca6d8713cea to before 58fcd1b156152613ba00a064a129fb69507ddd7d` (git)
  - affected: `17926a79320afa9b95df6b977b40cca6d8713cea to before fe4447cd95623b1cfacc15f280aab73a6d7340b2` (git)
  - Other versions: unaffected
- Vendor: Linux. Product: Linux.
  - affected: `2.6.22`
  - unaffected: `before 2.6.22` (semver)
  - unaffected: `5.10.258 to 5.10.*, inclusive` (semver)
  - unaffected: `5.15.209 to 5.15.*, inclusive` (semver)
  - unaffected: `6.1.175 to 6.1.*, inclusive` (semver)
  - unaffected: `6.6.135 to 6.6.*, inclusive` (semver)
  - unaffected: `6.12.82 to 6.12.*, inclusive` (semver)
  - unaffected: `6.18.23 to 6.18.*, inclusive` (semver)
  - unaffected: `6.19.13 to 6.19.*, inclusive` (semver)
  - unaffected: `7.0 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:** 0.0059, the 48th 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 24 Apr 2026. New records show when each source confirmed them.

## Sources

- [CVE List: CVE-2026-31637](https://www.cve.org/CVERecord?id=CVE-2026-31637)
- [NVD: CVE-2026-31637](https://nvd.nist.gov/vuln/detail/CVE-2026-31637)

### References from the CNA

- <https://git.kernel.org/stable/c/252157d939d179b5d767cb860ff8fa7f8723b67a>
- <https://git.kernel.org/stable/c/a75b3b361dd481d942c5f259a82d59718a41092c>
- <https://git.kernel.org/stable/c/b3a808cd0790b5075aaa2bc3588edf02cd71d352>
- <https://git.kernel.org/stable/c/47073aab8a3a5a7b41c9bd37d2a3dcbeeccd6c8a>
- <https://git.kernel.org/stable/c/a149dcae23309df9de1c3b6b5d468610ef5ab7de>
- <https://git.kernel.org/stable/c/22f6258e7b31dba9bf88dce4e3ee7f0f20072e60>
- <https://git.kernel.org/stable/c/58fcd1b156152613ba00a064a129fb69507ddd7d>
- <https://git.kernel.org/stable/c/fe4447cd95623b1cfacc15f280aab73a6d7340b2>

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-2026-31637>
- Everything that needs attention now: <https://agentprime.io/advisories/critical.md>

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The web page: <https://agentprime.io/advisories/CVE-2026-31637/>. Everything for agents: <https://agentprime.io/llms.txt>.