CVE-2026-33599

A rogue backend can send a crafted SVCB response to a Discovery of Designated Resolvers request, when requested via either the autoUpgrade (Lua) option to newServer or auto_upgrade (YAML) settings. DDR upgrade is not enabled by default.

More information : https://www.dnsdist.org/security-advisories/powerdns-advisory-for-dnsdist-2026-04.html