Auth bypass in OpenStack Designate
CVE-2026-71193
In OpenStack Designate before 22.0.1, zone creation checks (_is_subzone, _is_superzone, and the duplicate-zone DB constraint) are scoped to the target pool only. An authenticated user can bypass these checks by scheduling a zone to a different pool via the AttributeFilter scheduler, creating an overlapping zone that conflicts with another tenant's zone. This enables cross-tenant DNS hijack (redirecting traffic to attacker-controlled IPs) and DNS denial of service (NODATA responses). Exploitation requires a multi-pool deployment with AttributeFilter enabled in scheduler_filters, which is a non-default but documented and supported configuration for self-service tiering.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.6 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:H.
EPSS exploit prediction
EPSS: 0.005 (42.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 42nd percentile — 42.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.005 · change: +0.002
Affected products
- OpenStack Designate — versions 1.0.0, 21.0.0, 22.0.0
Weakness classification (CWE)
References
- launchpad.net/bugs/2160533 (issue-tracking)
- security.openstack.org/ossa/OSSA-2026-034.html (vendor-advisory)
- www.openwall.com/lists/oss-security/2026/08/11/6 (mailing-list, vendor-advisory)
Frequently asked questions
- What is CVE-2026-71193?
- CVE-2026-71193 is a critical-severity vulnerability in OpenStack Designate, classified under Incorrect Authorization. CVSS score: 9.6/10. Published 2026-08-12.
- How severe is CVE-2026-71193?
- Critical severity. CVSS v3 base score is 9.6 out of 10.