CVE-2026-54588: Poweradmin

Critical severity, CVSS 9.6. EPSS: 0.5% chance of exploitation in the next 30 days.

Poweradmin is a web-based DNS administration tool for PowerDNS server. Versions prior to 4.2.4 and 4.3.3 use the attacker-controlled `HTTP_HOST` request header as the authoritative source for building callback URLs in its OIDC, SAML, and logout authentication flows without any validation. An unauthenticated attacker can poison the `redirect_uri` sent to the Identity Provider, causing the IdP to redirect the victim's authorization code to an attacker-controlled server - resulting in full account takeover with no credentials required. Versions 4.2.4 and 4.3.3 patch the issue.

Affected products

• Poweradmin Poweradmin: before 4.2.4 (fixed in 4.2.4); from 4.3.0, before 4.3.3 (fixed in 4.3.3)

Published 2026-06-23. Last modified 2026-06-25.