Auth bypass in OpenStack Zaqar

CVE-2026-66139

OpenStack Zaqar through 22.0.0 allows authentication bypass via an EXTRA-SPEC header when a UUID is known.

Vulnerability class: Broken Authentication

Published · last modified .

CVSS v3 metric

CVSS v3 base score 4.8 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L.

EPSS exploit prediction

EPSS: 0.005 (41.4th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 41st percentile — 41.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-66139: held from 0.005 to 0.005.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-66139?
CVE-2026-66139 is a medium-severity vulnerability in OpenStack Zaqar, classified under Missing Authentication for Critical Function. CVSS score: 4.8/10. Published 2026-07-24.
How severe is CVE-2026-66139?
Medium severity. CVSS v3 base score is 4.8 out of 10.