CVE-2011-4528: Unbound

Medium severity, CVSS 5.0. EPSS: 2.8% chance of exploitation in the next 30 days.

Unbound before 1.4.13p2 attempts to free unallocated memory during processing of duplicate CNAME records in a signed zone, which allows remote DNS servers to cause a denial of service (daemon crash) via a crafted response.

Affected products

• Unbound Unbound: up to and including 1.4.13; version 0.0 only; version 0.1 only; version 0.2 only; version 0.3 only; version 0.4 only; …

Published 2011-12-20. Last modified 2026-06-16.