CVE-2026-33259: Powerdns Recursor

Medium severity, CVSS 5.0. EPSS: 0.3% chance of exploitation in the next 30 days.

Having many concurrent transfers of the same RPZ can lead to inconsistent RPZ data, use after free and/or a crash of the recursor. Normally concurrent transfers of the same RPZ zone can only occur with a malfunctioning RPZ provider.

Affected products

• Powerdns Recursor: from 5.2.0, before 5.2.9 (fixed in 5.2.9); from 5.3.0, before 5.3.6 (fixed in 5.3.6); version 5.4.0 only

Published 2026-04-22. Last modified 2026-06-17.