CVE-2026-66139 Auth bypass in Zaqar
Attackers can bypass authentication in OpenStack Zaqar by using a specific header if a UUID is known, requiring immediate patching.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-66139?
CVE-2026-66139 is a medium-severity authentication bypass vulnerability in OpenStack Zaqar, published on 24 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
OpenStack Zaqar through 22.0.0 allows authentication bypass via an EXTRA-SPEC header when a UUID is known.
Weakness: CWE-306
Which versions are affected by CVE-2026-66139?
How do I fix CVE-2026-66139?
Apply the vendor's patch.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-66139 being exploited?
There is no known exploitation of CVE-2026-66139 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-66139, GHSA-gmmh-575h-g7v8, UBUNTU-CVE-2026-66139.