GHSA-3735-5339-xfwx

Summary

Poweradmin v4.3.2 uses 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.

Three independent code paths are affected:

• Primary (Critical): OidcService::getCallbackUrl() - redirect_uri poisoning
• Secondary (High): SamlConfigurationService::getBaseUrl() - SAML ACS/SLO URL poisoning
• Tertiary (Medium): LogoutController::getBaseUrl() - post-logout redirect poisoning

Details

Root Cause

The application constructs absolute URLs dynamically from HTTP_HOST rather than from a trusted configured base URL. The header is fully client-controlled and is not validated before use in any authentication flow.

Poweradmin's own codebase contains the correct pattern - DocsController::getValidatedHost() (line 244) calls isValidHostname() before using the value - but this was never applied to authentication flows.

Primary: lib/Application/Service/OidcService.php (~line 460)

private function getCallbackUrl(): string
{
    $scheme = $this->detectScheme();
    // HTTP_HOST taken directly with zero validation
    $host = $this->request->getServerParam('HTTP_HOST', 'localhost');
    $basePrefix = $this->configManager->get('interface', 'base_url_prefix', '');
    return $scheme . '://' . $host . $basePrefix . '/oidc/callback';
}

HTTP_HOST is embedded verbatim as redirect_uri in the OAuth 2.0 authorization
request sent to the IdP. HTTP_X_FORWARDED_PROTO is similarly used unvalidated
for scheme detection.

Secondary: lib/Application/Service/SamlConfigurationService.php (~line 134)

private...