# tcp: fix potential race in tcp_v6_syn_recv_sock()

CVE record · `CVE-2026-43198`

- **Identifiers:** `CVE-2026-43198`
- **State:** Confirmed
- **Severity:** CVSS 9.8 Critical
- **Critical:** Yes: CVSS 9+
- **CNA:** Linux
- **Weakness (CWE):** [CWE-362](https://cwe.mitre.org/data/definitions/362.html) · [CWE-821](https://cwe.mitre.org/data/definitions/821.html)
- **Tags:** [Race condition](https://agentprime.io/advisories/tag/race-condition.md) · [CWE-821](https://agentprime.io/advisories/tag/cwe-821.md)
- **Technologies:** [Linux kernel](https://agentprime.io/advisories/technology/linux-kernel.md)
- **Published:** 6 May 2026
- **Updated:** 19 Oct 2026
- **Reviewed by a person:** No

Published by the CVE Program (CNA: Linux) at 6 May 2026, 11:28 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: `1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before aef4a9ae95d1bc4f7897065011e6261026719aeb` (git)
  - affected: `1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before dad1fe7db6c6519138430ac8f5e589c18f83bfc9` (git)
  - affected: `1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before a7e761ba55efaa9c49e0afdd304bb78167af3429` (git)
  - affected: `1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before cd644e6dc72eec8d9d988717ea1c54f8668ded69` (git)
  - affected: `1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before 9ed654e340f4c73bc6f0af2fbc90ac293e645ce0` (git)
  - affected: `1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before fe89b2f05b854847784f91127319172945c1fadd` (git)
  - affected: `1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before 7178e2a8027423b2af17ab95df73a749a5b72e5b` (git)
  - affected: `1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before 858d2a4f67ff69e645a43487ef7ea7f28f06deae` (git)
  - Other versions: unaffected
- Vendor: Linux. Product: Linux.
  - affected: `2.6.12`
  - unaffected: `before 2.6.12` (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: `6.18.16 to 6.18.*, inclusive` (semver)
  - unaffected: `6.19.6 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) (used for this record)
- 7.0 High, CVSS 3.1: `CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H`, from ADP (redhat-SADP)

- **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 6 May 2026. New records show when each source confirmed them.

## Sources

- [CVE List: CVE-2026-43198](https://www.cve.org/CVERecord?id=CVE-2026-43198)
- [NVD: CVE-2026-43198](https://nvd.nist.gov/vuln/detail/CVE-2026-43198)

### References from the CNA

- <https://git.kernel.org/stable/c/aef4a9ae95d1bc4f7897065011e6261026719aeb>
- <https://git.kernel.org/stable/c/dad1fe7db6c6519138430ac8f5e589c18f83bfc9>
- <https://git.kernel.org/stable/c/a7e761ba55efaa9c49e0afdd304bb78167af3429>
- <https://git.kernel.org/stable/c/cd644e6dc72eec8d9d988717ea1c54f8668ded69>
- <https://git.kernel.org/stable/c/9ed654e340f4c73bc6f0af2fbc90ac293e645ce0>
- <https://git.kernel.org/stable/c/fe89b2f05b854847784f91127319172945c1fadd>
- <https://git.kernel.org/stable/c/7178e2a8027423b2af17ab95df73a749a5b72e5b>
- <https://git.kernel.org/stable/c/858d2a4f67ff69e645a43487ef7ea7f28f06deae>

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-2026-43198>
- Everything that needs attention now: <https://agentprime.io/advisories/critical.md>

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The web page: <https://agentprime.io/advisories/CVE-2026-43198/>. Everything for agents: <https://agentprime.io/llms.txt>.