# Keycloak has an Authentication Bypass by Primary Weakness

Advisory record · `GHSA-q6h7-xxp7-7429`

- **Identifiers:** `GHSA-q6h7-xxp7-7429` · `CVE-2026-9798`
- **State:** Confirmed
- **Severity:** CVSS 4.3 Medium
- **Critical:** No
- **Weakness (CWE):** [CWE-305](https://cwe.mitre.org/data/definitions/305.html)
- **Tags:** [CWE-305](https://agentprime.io/advisories/tag/cwe-305.md)
- **Published:** 28 May 2026
- **Updated:** 10 Sept 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-services` (Maven): affected `<=26.4.7 || >=26.5.0, <=26.6.4`; no fixed version yet

## Machine-written summary

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

> Keycloak (Maven package org.keycloak:keycloak-services, versions up to 26.4.7, 26.5.0 through 26.6.4) is affected. An attacker who holds valid client credentials can use the CIBA flow to get past brute-force lockout on a temporarily locked user account, continuing login attempts and token issuance. No fixed version is listed, and the source gives few details on workarounds.

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

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

- **CISA KEV:** Not listed.
- **EPSS:** 0.0037, the 31st percentile, on 6 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 31 Oct 2026, 14:16 UTC: First seen by agentprime
- 31 Oct 2026, 14:16 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-q6h7-xxp7-7429)

## Sources

- [GitHub Advisory Database: GHSA-q6h7-xxp7-7429](https://github.com/advisories/GHSA-q6h7-xxp7-7429)
- [OSV: GHSA-q6h7-xxp7-7429](https://osv.dev/vulnerability/GHSA-q6h7-xxp7-7429)
- <https://nvd.nist.gov/vuln/detail/CVE-2026-9798>
- <https://github.com/keycloak/keycloak/issues/49432>
- <https://github.com/keycloak/keycloak/pull/49791>
- <https://github.com/keycloak/keycloak/pull/49903>
- <https://github.com/keycloak/keycloak/pull/49905>
- <https://github.com/keycloak/keycloak/commit/11c2695064cd93da1d333df3f69d4a4141e86c29>
- <https://github.com/keycloak/keycloak/commit/2edc6b112e2dedce63062b89ab3c7ae542e0d9ac>
- <https://github.com/keycloak/keycloak/commit/a11e3254efc16ae72ce5092b93b9f557a4ba43ae>
- <https://access.redhat.com/errata/RHSA-2026:50846>
- <https://access.redhat.com/errata/RHSA-2026:50847>
- <https://access.redhat.com/errata/RHSA-2026:50848>
- <https://access.redhat.com/errata/RHSA-2026:50849>

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-q6h7-xxp7-7429>, 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-q6h7-xxp7-7429/>. Everything for agents: <https://agentprime.io/llms.txt>.