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GHSA-3735-5339-XFWX

Vulnerability from github – Published: 2026-07-28 16:40 – Updated: 2026-07-28 16:40
VLAI
Summary
Poweradmin has Host Header Injection in OIDC redirect_uri, SAML ACS/SLO URL, and Logout Redirect Construction.
Details

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)

```php 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 function getBaseUrl(): string { $configuredBaseUrl = $this->configManager->get('interface', 'base_url', ''); if (!empty($configuredBaseUrl)) { return rtrim($configuredBaseUrl, '/'); // safe path - rarely configured } // Falls through on every default installation $host = $_SERVER['HTTP_HOST'] ?? 'localhost'; ... return $scheme . '://' . $host . $prefix; }

Used to construct SAML ACS URL, SLO URL, and entity ID - all poisonable via Host header. The safe fallback only activates when interface.base_url is explicitly set, which is optional and empty by default.

Tertiary: lib/Application/Controller/LogoutController.php (~line 272)

Same $_SERVER['HTTP_HOST'] pattern used for post-logout redirect URL construction.

PoC

Environment: Poweradmin v4.3.2, Docker, PHP 8.2, OIDC enabled, interface.base_url empty (default).

docker exec poweradmin-container php -r " require '/app/vendor/autoload.php'; putenv('PA_CONFIG_PATH=/app/config/settings.php');

use PowerAdmin\Application\Service\OidcService; use PowerAdmin\Infrastructure\Configuration\ConfigurationManager; use PowerAdmin\Infrastructure\Web\Request;

\$_SERVER['HTTP_HOST'] = 'attacker.com'; \$_SERVER['HTTPS'] = '';

\$config = ConfigurationManager::getInstance(); \$request = new Request(); \$oidcService = new OidcService(\$config, \$request); \$authUrl = \$oidcService->initiateAuthFlow('test');

parse_str(parse_url(\$authUrl, PHP_URL_QUERY), \$p); echo 'redirect_uri: ' . urldecode(\$p['redirect_uri']) . PHP_EOL;

if (str_contains(\$p['redirect_uri'], 'attacker.com')) { echo '[CONFIRMED] Host header injection successful' . PHP_EOL; } "

Output:

redirect_uri: http://attacker.com/oidc/callback

[CONFIRMED] Host header injection successful - redirect_uri contains attacker.com

The redirect_uri in the authorization request sent to the Identity Provider is http://attacker.com/oidc/callback. The victim's authorization code will be delivered to this URL upon successful authentication.

Note on PKCE: PKCE does not mitigate this attack. The attacker initiates the flow themselves and controls both code_challenge and code_verifier.

Impact

Direct Impact

An attacker who can send a request with a spoofed Host header - directly or via a misconfigured reverse proxy (proxy_set_header Host $http_host is the nginx default) - can steal any user's authorization code and gain full authenticated access to Poweradmin. No credentials, malware, or prior access required.

DNS Infrastructure Impact

Poweradmin manages PowerDNS. A compromised administrator account grants full DNS zone control, enabling:

  • MX hijacking - redirect all inbound email to attacker's mail server; intercept password reset emails and 2FA codes for any third-party service registered with the domain
  • SPF/DKIM manipulation - add attacker's IP to SPF, publish attacker's DKIM key → send cryptographically authenticated email as the organization (passes DMARC)
  • Subdomain takeover - point mail., vpn., app. to attacker infrastructure
  • SSL certificate theft - remove CAA records and complete ACME DNS-01 challenge to obtain wildcard certificate *.company.com from any CA
  • Full domain delegation - delegate subdomains to attacker nameserver

CVSS v3.1

┌──────────────────────────────────┬─────────────────────────────────────┬──────────────┐ │ Scenario │ Vector │ Score │ ├──────────────────────────────────┼─────────────────────────────────────┼──────────────┤ │ Standard deployment │ AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L │ 8.2 High │ ├──────────────────────────────────┼─────────────────────────────────────┼──────────────┤ │ Proxy misconfigured ($http_host) │ AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:L │ 9.3 Critical │ └──────────────────────────────────┴─────────────────────────────────────┴──────────────┘

Recommended Fix

Immediate mitigation: Set interface.base_url in config/settings.php - activates the safe branch in SamlConfigurationService immediately.

Code fix for OidcService: Prefer the configured base URL; if absent, validate HTTP_HOST via filter_var($hostname, FILTER_VALIDATE_DOMAIN, FILTER_FLAG_HOSTNAME) before use - the same pattern already implemented in DocsController::getValidatedHost().

Show details on source website

{
  "affected": [
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "poweradmin/poweradmin"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.2.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "poweradmin/poweradmin"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.3.0"
            },
            {
              "fixed": "4.3.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-54588"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-601"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-07-28T16:40:05Z",
    "nvd_published_at": "2026-06-23T23:16:49Z",
    "severity": "CRITICAL"
  },
  "details": "### Summary\nPoweradmin v4.3.2 uses the attacker-controlled `HTTP_HOST` request header as the\n  authoritative source for building callback URLs in its OIDC, SAML, and logout\n  authentication flows without any validation. An unauthenticated attacker can poison\n  the `redirect_uri` sent to the Identity Provider, causing the IdP to redirect the\n  victim\u0027s authorization code to an attacker-controlled server - resulting in full\n  account takeover with no credentials required.\n\n  Three independent code paths are affected:\n\n  - **Primary (Critical):** `OidcService::getCallbackUrl()` - `redirect_uri` poisoning\n  - **Secondary (High):** `SamlConfigurationService::getBaseUrl()` - SAML ACS/SLO URL poisoning\n  - **Tertiary (Medium):** `LogoutController::getBaseUrl()` - post-logout redirect poisoning\n\n### Details\n\n***Root Cause***\n\n  The application constructs absolute URLs dynamically from `HTTP_HOST` rather than\n  from a trusted configured base URL. The header is fully client-controlled and is not\n  validated before use in any authentication flow.\n\n  Poweradmin\u0027s own codebase contains the correct pattern -\n  `DocsController::getValidatedHost()` (line 244) calls `isValidHostname()` before\n  using the value - but this was never applied to authentication flows.\n\n  ### Primary: `lib/Application/Service/OidcService.php` (~line 460)\n\n  ```php\n  private function getCallbackUrl(): string\n  {\n      $scheme = $this-\u003edetectScheme();\n      // HTTP_HOST taken directly with zero validation\n      $host = $this-\u003erequest-\u003egetServerParam(\u0027HTTP_HOST\u0027, \u0027localhost\u0027);\n      $basePrefix = $this-\u003econfigManager-\u003eget(\u0027interface\u0027, \u0027base_url_prefix\u0027, \u0027\u0027);\n      return $scheme . \u0027://\u0027 . $host . $basePrefix . \u0027/oidc/callback\u0027;\n  }\n\n  HTTP_HOST is embedded verbatim as redirect_uri in the OAuth 2.0 authorization\n  request sent to the IdP. HTTP_X_FORWARDED_PROTO is similarly used unvalidated\n  for scheme detection.\n\n  Secondary: lib/Application/Service/SamlConfigurationService.php (~line 134)\n\n  private function getBaseUrl(): string\n  {\n      $configuredBaseUrl = $this-\u003econfigManager-\u003eget(\u0027interface\u0027, \u0027base_url\u0027, \u0027\u0027);\n      if (!empty($configuredBaseUrl)) {\n          return rtrim($configuredBaseUrl, \u0027/\u0027);  // safe path - rarely configured\n      }\n      // Falls through on every default installation\n      $host = $_SERVER[\u0027HTTP_HOST\u0027] ?? \u0027localhost\u0027;\n      ...\n      return $scheme . \u0027://\u0027 . $host . $prefix;\n  }\n\n  Used to construct SAML ACS URL, SLO URL, and entity ID - all poisonable via Host header.\n  The safe fallback only activates when interface.base_url is explicitly set, which is\n  optional and empty by default.\n\n  Tertiary: lib/Application/Controller/LogoutController.php (~line 272)\n\n  Same $_SERVER[\u0027HTTP_HOST\u0027] pattern used for post-logout redirect URL construction.\n\n### PoC\nEnvironment: Poweradmin v4.3.2, Docker, PHP 8.2, OIDC enabled, interface.base_url empty (default).\n\n  docker exec poweradmin-container php -r \"\n  require \u0027/app/vendor/autoload.php\u0027;\n  putenv(\u0027PA_CONFIG_PATH=/app/config/settings.php\u0027);\n\n  use PowerAdmin\\Application\\Service\\OidcService;\n  use PowerAdmin\\Infrastructure\\Configuration\\ConfigurationManager;\n  use PowerAdmin\\Infrastructure\\Web\\Request;\n\n  \\$_SERVER[\u0027HTTP_HOST\u0027] = \u0027attacker.com\u0027;\n  \\$_SERVER[\u0027HTTPS\u0027]     = \u0027\u0027;\n\n  \\$config      = ConfigurationManager::getInstance();\n  \\$request     = new Request();\n  \\$oidcService = new OidcService(\\$config, \\$request);\n  \\$authUrl     = \\$oidcService-\u003einitiateAuthFlow(\u0027test\u0027);\n\n  parse_str(parse_url(\\$authUrl, PHP_URL_QUERY), \\$p);\n  echo \u0027redirect_uri: \u0027 . urldecode(\\$p[\u0027redirect_uri\u0027]) . PHP_EOL;\n\n  if (str_contains(\\$p[\u0027redirect_uri\u0027], \u0027attacker.com\u0027)) {\n      echo \u0027[CONFIRMED] Host header injection successful\u0027 . PHP_EOL;\n  }\n  \"\n\n  Output:\n\n  redirect_uri: http://attacker.com/oidc/callback\n\n  [CONFIRMED] Host header injection successful - redirect_uri contains attacker.com\n\n  The redirect_uri in the authorization request sent to the Identity Provider is\n  http://attacker.com/oidc/callback. The victim\u0027s authorization code will be\n  delivered to this URL upon successful authentication.\n\n  Note on PKCE: PKCE does not mitigate this attack. The attacker initiates the\n  flow themselves and controls both code_challenge and code_verifier.\n\n### Impact\nDirect Impact\n\n  An attacker who can send a request with a spoofed Host header - directly or via a\n  misconfigured reverse proxy (proxy_set_header Host $http_host is the nginx default) -\n  can steal any user\u0027s authorization code and gain full authenticated access to Poweradmin.\n  No credentials, malware, or prior access required.\n\n  DNS Infrastructure Impact\n\n  Poweradmin manages PowerDNS. A compromised administrator account grants full DNS zone\n  control, enabling:\n\n  - MX hijacking - redirect all inbound email to attacker\u0027s mail server; intercept\n  password reset emails and 2FA codes for any third-party service registered with the domain\n  - SPF/DKIM manipulation - add attacker\u0027s IP to SPF, publish attacker\u0027s DKIM key \u2192\n  send cryptographically authenticated email as the organization (passes DMARC)\n  - Subdomain takeover - point mail., vpn., app. to attacker infrastructure\n  - SSL certificate theft - remove CAA records and complete ACME DNS-01 challenge\n  to obtain wildcard certificate *.company.com from any CA\n  - Full domain delegation - delegate subdomains to attacker nameserver\n\n  CVSS v3.1\n\n  \u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u252c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u252c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510\n  \u2502             Scenario             \u2502               Vector                \u2502    Score     \u2502\n  \u251c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u253c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u253c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2524\n  \u2502 Standard deployment              \u2502 AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L \u2502 8.2 High     \u2502\n  \u251c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u253c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u253c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2524\n  \u2502 Proxy misconfigured ($http_host) \u2502 AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:L \u2502 9.3 Critical \u2502\n  \u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2534\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2534\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518\n\n  Recommended Fix\n\n  Immediate mitigation: Set interface.base_url in config/settings.php -\n  activates the safe branch in SamlConfigurationService immediately.\n\n  Code fix for OidcService: Prefer the configured base URL; if absent, validate\n  HTTP_HOST via filter_var($hostname, FILTER_VALIDATE_DOMAIN, FILTER_FLAG_HOSTNAME)\n  before use - the same pattern already implemented in DocsController::getValidatedHost().",
  "id": "GHSA-3735-5339-xfwx",
  "modified": "2026-07-28T16:40:05Z",
  "published": "2026-07-28T16:40:05Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/poweradmin/poweradmin/security/advisories/GHSA-3735-5339-xfwx"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-54588"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/poweradmin/poweradmin"
    },
    {
      "type": "WEB",
      "url": "https://github.com/poweradmin/poweradmin/releases/tag/v4.2.4"
    },
    {
      "type": "WEB",
      "url": "https://github.com/poweradmin/poweradmin/releases/tag/v4.3.3"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Poweradmin has Host Header Injection in OIDC redirect_uri, SAML ACS/SLO URL, and Logout Redirect Construction."
}



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