GHSA-v897-pv23-r8cw
Keycloak has an improper input validation vulnerability
At a glance
- Published
- Updated
- CVE
- CVE-2026-0976
- CVSS_V3
- CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
Description
A flaw was found in Keycloak. This improper input validation vulnerability occurs because Keycloak accepts RFC-compliant matrix parameters in URL path segments, while common reverse proxy configurations may ignore or mishandle them. A remote attacker can craft requests to mask path segments, potentially bypassing proxy-level path filtering. This could expose administrative or sensitive endpoints that operators believe are not externally reachable.
Affected packages
| Package | Versions |
|---|---|
| Maven · org.keycloak:keycloak-quarkus-server | introduced 0, last affected 26.2.5 |
References
- https://nvd.nist.gov/vuln/detail/CVE-2026-0976 ADVISORY
- https://access.redhat.com/errata/RHSA-2026:2365 WEB
- https://access.redhat.com/security/cve/CVE-2026-0976 WEB
- https://bugzilla.redhat.com/show_bug.cgi?id=2429869 WEB
- https://github.com/keycloak/keycloak PACKAGE
Sources
| Source | Licence |
|---|---|
| OSV.dev | CC-BY 4.0 — GitHub Advisory Database |