# netfilter: xt_policy: fix strict mode inbound policy matching

CVE record · `CVE-2026-52920`

- **Identifiers:** `CVE-2026-52920`
- **State:** Confirmed
- **Severity:** CVSS 8.3 High
- **Critical:** No
- **CNA:** Linux
- **Weakness (CWE):** [CWE-682](https://cwe.mitre.org/data/definitions/682.html)
- **Tags:** [CWE-682](https://agentprime.io/advisories/tag/cwe-682.md)
- **Technologies:** [Linux kernel](https://agentprime.io/advisories/technology/linux-kernel.md)
- **Published:** 24 Jun 2026
- **Updated:** 19 Oct 2026
- **Reviewed by a person:** No

Published by the CVE Program (CNA: Linux) at 24 Jun 2026, 07:14 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: `c4b885139203d37f76662c37ae645fe8e0f4e4e5 to before eb323f7b82d2e2f638de0cc2a177803eb20e0707` (git)
  - affected: `c4b885139203d37f76662c37ae645fe8e0f4e4e5 to before fc1c518bb1f054831ecabb32da9b8e1dff9699c6` (git)
  - affected: `c4b885139203d37f76662c37ae645fe8e0f4e4e5 to before f98b7f85e04b40e28b08c461ded0cc79f14f5509` (git)
  - affected: `c4b885139203d37f76662c37ae645fe8e0f4e4e5 to before 82664d0f1ba25e4f9a71994954abae24c60f4067` (git)
  - affected: `c4b885139203d37f76662c37ae645fe8e0f4e4e5 to before b130a6eefa02bd4d475f2f059da8bcfb3e7d18d9` (git)
  - affected: `c4b885139203d37f76662c37ae645fe8e0f4e4e5 to before 938867e870fb5471bb16f442aeac81326e05bf65` (git)
  - affected: `c4b885139203d37f76662c37ae645fe8e0f4e4e5 to before 392cc1d8408b5665215c1e9290bbf0f92339b043` (git)
  - affected: `c4b885139203d37f76662c37ae645fe8e0f4e4e5 to before 4b2b4d7d4e203c92db8966b163edfacb1f0e1e29` (git)
  - Other versions: unaffected
- Vendor: Linux. Product: Linux.
  - affected: `2.6.17`
  - unaffected: `before 2.6.17` (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: `6.6.141 to 6.6.*, inclusive` (semver)
  - unaffected: `6.12.91 to 6.12.*, inclusive` (semver)
  - unaffected: `6.18.33 to 6.18.*, inclusive` (semver)
  - unaffected: `7.0.10 to 7.0.*, inclusive` (semver)
  - unaffected: `7.1 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

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

- **CISA KEV:** Not listed.
- **EPSS:** 0.0030, the 22nd percentile, on 5 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 Jun 2026. New records show when each source confirmed them.

## Sources

- [CVE List: CVE-2026-52920](https://www.cve.org/CVERecord?id=CVE-2026-52920)
- [NVD: CVE-2026-52920](https://nvd.nist.gov/vuln/detail/CVE-2026-52920)

### References from the CNA

- <https://git.kernel.org/stable/c/eb323f7b82d2e2f638de0cc2a177803eb20e0707>
- <https://git.kernel.org/stable/c/fc1c518bb1f054831ecabb32da9b8e1dff9699c6>
- <https://git.kernel.org/stable/c/f98b7f85e04b40e28b08c461ded0cc79f14f5509>
- <https://git.kernel.org/stable/c/82664d0f1ba25e4f9a71994954abae24c60f4067>
- <https://git.kernel.org/stable/c/b130a6eefa02bd4d475f2f059da8bcfb3e7d18d9>
- <https://git.kernel.org/stable/c/938867e870fb5471bb16f442aeac81326e05bf65>
- <https://git.kernel.org/stable/c/392cc1d8408b5665215c1e9290bbf0f92339b043>
- <https://git.kernel.org/stable/c/4b2b4d7d4e203c92db8966b163edfacb1f0e1e29>

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-2026-52920>
- Everything that needs attention now: <https://agentprime.io/advisories/critical.md>

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The web page: <https://agentprime.io/advisories/CVE-2026-52920/>. Everything for agents: <https://agentprime.io/llms.txt>.