# SUNRPC: wait for in-flight client TLS handshake callback

CVE record · `CVE-2026-89536`

- **Identifiers:** `CVE-2026-89536`
- **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:** 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.

## 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: `75eb6af7acdf566c68d61e98e67ee2f235201c02 to before fb43997407bc17ee39bac81ab708101312e255f5` (git)
  - affected: `75eb6af7acdf566c68d61e98e67ee2f235201c02 to before 15431820f448e09f8029b670d5c82aa5917d4625` (git)
  - affected: `75eb6af7acdf566c68d61e98e67ee2f235201c02 to before 1de391e8b94e31b45c19c16dbf315e294810c7de` (git)
  - affected: `75eb6af7acdf566c68d61e98e67ee2f235201c02 to before 7fbb6d2ab0391eb8d1f1a68e6bc263ef02cea61b` (git)
  - affected: `75eb6af7acdf566c68d61e98e67ee2f235201c02 to before a89dd597458848b463d284b15e42a8078beeb046` (git)
  - Other versions: unaffected
- Vendor: Linux. Product: Linux.
  - affected: `6.5`
  - unaffected: `before 6.5` (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

- 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:** 0.0063, the 51st 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-2026-89536](https://www.cve.org/CVERecord?id=CVE-2026-89536)
- [NVD: CVE-2026-89536](https://nvd.nist.gov/vuln/detail/CVE-2026-89536)

### References from the CNA

- <https://git.kernel.org/stable/c/fb43997407bc17ee39bac81ab708101312e255f5>
- <https://git.kernel.org/stable/c/15431820f448e09f8029b670d5c82aa5917d4625>
- <https://git.kernel.org/stable/c/1de391e8b94e31b45c19c16dbf315e294810c7de>
- <https://git.kernel.org/stable/c/7fbb6d2ab0391eb8d1f1a68e6bc263ef02cea61b>
- <https://git.kernel.org/stable/c/a89dd597458848b463d284b15e42a8078beeb046>

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-2026-89536>
- Everything that needs attention now: <https://agentprime.io/advisories/critical.md>

---

The web page: <https://agentprime.io/advisories/CVE-2026-89536/>. Everything for agents: <https://agentprime.io/llms.txt>.