GitHub Security Advisory Draft — GM-374

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 12.3.6"
      },
      "package": {
        "ecosystem": "Packagist",
        "name": "pimcore/pimcore"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "12.0.0-RC1"
            },
            {
              "fixed": "12.3.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 11.5.16"
      },
      "package": {
        "ecosystem": "Packagist",
        "name": "pimcore/pimcore"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "11.5.17"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "pimcore/pimcore"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2026.1.0"
            },
            {
              "fixed": "2026.1.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-45162"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-502"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-27T16:57:04Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "# GitHub Security Advisory Draft \u2014 GM-374\n\n## Summary\nMultiple locations in Pimcore v11 call PHP\u0027s `unserialize()` on data from database columns and filesystem files without the `allowed_classes` restriction, enabling object injection if an attacker can control the serialized data source.\n\n## Severity\nCVSS 3.1: 8.0 (High) \u2014 AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H\n\n## Affected Component\n- **Package:** `pimcore/pimcore` and `pimcore/admin-ui-classic-bundle`\n- **Files:**\n  - `lib/Tool/Authentication.php` (line 82) \u2014 session token deserialization\n  - `models/Site/Dao.php` (line 68) \u2014 site domains from database\n  - `models/DataObject/ClassDefinition/CustomLayout/Dao.php` (line 69) \u2014 layout definitions from database\n  - `models/Tool/TmpStore/Dao.php` (line 64) \u2014 temporary store data from database\n  - `models/Asset/WebDAV/Service.php` (line 36) \u2014 delete log from filesystem\n  - `admin-ui-classic-bundle/src/Helper/Dashboard.php` (line 64) \u2014 dashboard config from filesystem\n\n## Description\nSix locations in Pimcore core call `unserialize()` directly (bypassing `Tool\\Serialize`) on data sourced from database columns or filesystem files without passing the `allowed_classes` parameter. This means any class available in the autoloader will be instantiated during deserialization.\n\nIf an attacker can write to the data source (e.g., via SQL injection targeting the `tmp_store`, `sites`, or `custom_layouts` tables, or via a file write vulnerability targeting the WebDAV delete log), they can inject serialized PHP gadget chains that execute arbitrary code when the data is deserialized.\n\nThis is related to but distinct from the `Tool\\Serialize::unserialize()` issue \u2014 these calls bypass the wrapper entirely.\n\n## Impact\nPHP object injection leading to Remote Code Execution when chained with a data source write vulnerability. Pimcore\u0027s dependency tree (Guzzle, Symfony, Monolog, Doctrine) provides numerous known gadget chains.\n\n## Proof of Concept\n1. Identify a writable data source (e.g., `tmp_store` table via SQL injection, or `webdav-delete.dat` via file write)\n2. Write a serialized PHP gadget chain (e.g., Monolog `BufferHandler` chain from phpggc)\n3. Trigger the deserialization (e.g., access a page that reads TmpStore, or trigger a WebDAV operation)\n4. The gadget chain executes with web server privileges\n\n## Suggested Fix\nAdd `allowed_classes` parameter to all `unserialize()` calls. Where no objects are needed, use `[\u0027allowed_classes\u0027 =\u003e false]`. Consider migrating to JSON serialization for data that doesn\u0027t require object preservation.\n\n```php\n// Example fix for Site/Dao.php:\n$siteDomains = unserialize($site[\u0027domains\u0027], [\u0027allowed_classes\u0027 =\u003e false]);\n\n// Example fix for TmpStore/Dao.php:\n$item[\u0027data\u0027] = unserialize($item[\u0027data\u0027], [\u0027allowed_classes\u0027 =\u003e false]);\n```\n\n## References\n- CWE-502: Deserialization of Untrusted Data\n- OWASP Deserialization Cheat Sheet\n- phpggc: PHP Generic Gadget Chains",
  "id": "GHSA-36fc-7wjg-mfvj",
  "modified": "2026-07-10T19:07:27Z",
  "published": "2026-05-27T16:57:04Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/pimcore/pimcore/security/advisories/GHSA-36fc-7wjg-mfvj"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pimcore/pimcore/pull/19119"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pimcore/pimcore/commit/4788bf3a3a7f2f760a8fe61e522565941e154e1e"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/pimcore/pimcore"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pimcore/pimcore/releases/tag/v12.3.7"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Pimcore has Unsafe PHP Deserialization in Multiple Locations Without allowed_classes Restriction"
}