CVE-2026-42387: Powerdns Recursor

Medium severity, CVSS 5.9. EPSS: 0.5% chance of exploitation in the next 30 days.

A malicious authoritative server can send a crafted zone via the ZoneToCache function that leads to a crash of the Recursor due to insuffcient input validation.

Affected products

• Powerdns Recursor: from 5.2.0, before 5.2.11 (fixed in 5.2.11); from 5.3.0, before 5.3.8 (fixed in 5.3.8); from 5.4.0, before 5.4.3 (fixed in 5.4.3)

Published 2026-06-25. Last modified 2026-06-25.