Cross-tenant DNS zone overlap in OpenStack Designate (CVE-2026-71193)

OpenStack Designate fails to enforce cross-pool zone ownership checks when scheduling a zone to a non-default pool via the attribute filter. An authenticated tenant can create a sub-zone, super-zone, or duplicate of another tenant's zone by targeting a different pool, enabling DNS hijacking or denial of service. Separately, the mDNS handler performs pool-blind record lookups, causing deterministic denial of service when colliding zones exist across pools. Affected versions: - >=1.0.0 <20.0.2 - ==21.0.0 - ==22.0.0 We recommend updating to: 20.0.2. CVSS 9.6 · our assessment: act_now Reference: https://security.openstack.org/ossa/OSSA-2026-034.html Details: https://vuln.today/cve/CVE-2026-71193