VulnerabilityDeferred

CVE-2026-54588

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.

CRITICAL 9.6EPSS 0.54%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.54%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

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.

CVSS 3.1: 9.6 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L
EPSS: 0.54% probability · 44th percentile
CISA KEV: Not listed
Weakness: CWE-20, CWE-601
Source: security-advisories@github.com

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.