# Keycloak has a Time-of-check Time-of-use (TOCTOU) Race Condition

Advisory record · `GHSA-pq65-77rc-7r8c`

- **Identifiers:** `GHSA-pq65-77rc-7r8c` · `CVE-2026-9796`
- **State:** Confirmed
- **Severity:** CVSS 6.5 Medium
- **Critical:** No
- **Weakness (CWE):** [CWE-367](https://cwe.mitre.org/data/definitions/367.html)
- **Tags:** [Race condition](https://agentprime.io/advisories/tag/race-condition.md)
- **Published:** 28 May 2026
- **Updated:** 19 Aug 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 28 May 2026, 06:31 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `org.keycloak:keycloak-server` (Maven): affected `<26.6.4`; fixed in `26.6.4`

## Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

> Keycloak (Maven package org.keycloak:keycloak-server) versions before 26.6.4 are affected. An authenticated administrator holding the manage-clients role can exploit a time-of-check to time-of-use race condition in name-based admin role checks to escalate privileges to realm-admin for all users in the realm. The resulting composite role persists after the attacker's own permissions are revoked and across restarts. Upgrade to version 26.6.4.

Written 2 Nov 2026.

## Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

## Severity and exploitation

- 6.5 Medium, CVSS 3.1: `CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N`, from CNA (redhat)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0022, the 12th percentile, on 10 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 31 Oct 2026, 14:19 UTC: First seen by agentprime
- 31 Oct 2026, 14:19 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-pq65-77rc-7r8c)

## Sources

- [GitHub Advisory Database: GHSA-pq65-77rc-7r8c](https://github.com/advisories/GHSA-pq65-77rc-7r8c)
- [OSV: GHSA-pq65-77rc-7r8c](https://osv.dev/vulnerability/GHSA-pq65-77rc-7r8c)
- <https://nvd.nist.gov/vuln/detail/CVE-2026-9796>
- <https://github.com/keycloak/keycloak/issues/49427>
- <https://github.com/keycloak/keycloak/pull/49624>
- <https://github.com/keycloak/keycloak/commit/39cb8de54c8517efeda4baa8bc314fd40e9c6934>
- <https://access.redhat.com/errata/RHSA-2026:56523>
- <https://access.redhat.com/errata/RHSA-2026:56524>
- <https://access.redhat.com/security/cve/CVE-2026-9796>
- <https://bugzilla.redhat.com/show_bug.cgi?id=2482464>
- <https://github.com/keycloak/keycloak>

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.

## Check whether this affects you

A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: <https://agentprime.io/mcp.md>
- In a browser: <https://agentprime.io/check/> reads your lockfile in the browser, never uploading it.
- Whether it touches your code, with file and line: the Claude Code plugin, <https://agentprime.io/plugin.md>
- As JSON: <https://api.agentprime.io/v1/advisories/GHSA-pq65-77rc-7r8c>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

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The web page: <https://agentprime.io/advisories/GHSA-pq65-77rc-7r8c/>. Everything for agents: <https://agentprime.io/llms.txt>.