CVE-2026-0707 Keycloak: keycloak authorization header parsing leading to potential security control bypass
Attackers can bypass security controls by exploiting overly permissive Bearer token header parsing in Keycloak.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-0707?
CVE-2026-0707 is a medium-severity vulnerability in Red Hat build of Keycloak 26.4, published on 8 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A flaw was found in Keycloak. The Keycloak Authorization header parser is overly permissive regarding the formatting of the "Bearer" authentication scheme. It accepts non-standard characters (such as tabs) as separators and tolerates case variations that deviate from RFC 6750 specifications.
Weakness: CWE-551
Which versions are affected by CVE-2026-0707?
2 open source packages ship an affected version, including org.keycloak:keycloak-parent.
| Package | Affected | Fixed in |
|---|---|---|
org.keycloak:keycloak-parent Maven | All versions to 26.5.0 | None |
org.keycloak:keycloak-parent Maven | All versions to 26.5.0 | None |
How do I fix CVE-2026-0707?
No fix has been published for CVE-2026-0707 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-0707 being exploited?
There is no known exploitation of CVE-2026-0707 in the wild and no public exploit code.
Sources
Also known as GHSA-gv94-wp4h-vv8p.