{
  "affected": [
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "craftcms/cms"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "5.0.0-RC1"
            },
            {
              "fixed": "5.10.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "craftcms/cms"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.0.0-RC1"
            },
            {
              "fixed": "4.18.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [],
  "database_specific": {
    "cwe_ids": [
      "CWE-915"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-08-06T20:45:00Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "Craft CMS has an authenticated remote code execution issue in the control panel element-search condition handling.\n\nCraft cleans the outer request-controlled condition array with `Component::cleanseConfig()`, but `Conditions::createCondition()` later decodes and merges the JSON string in `condition.config` without re-running `cleanseConfig()` on the decoded/merged configuration.\n\nBecause `condition.config` is a JSON string during the first cleanse, Yii special config keys such as `as` ... and `on` ... can be hidden inside it. After JSON decoding, those keys reach FieldLayout object creation and are interpreted by Yii as behavior/event configuration.\n\nThe RCE is semi-blind: the trigger endpoint returns a normal JSON response, and the command output is verified via a server-side file-write side effect retrieved in a subsequent request.\n\n## Preconditions\n\n- The attacker needs an authenticated Craft control panel session.\n- A valid CSRF token is required.\n\n## Impact\n\nAn authenticated control panel user can inject Yii behavior/event configuration after Craft\u2019s intended config cleanse boundary. In the confirmed local lab, this led to command execution as the PHP/web user.\n\nPotential attacker impact:\n- Execute operating system commands as the PHP/web user.\n- Read Craft secrets, environment variables, and application configuration.\n- Access database credentials and stored site content.\n- Modify site content, users, and application state.\n- Pivot to internal services reachable from the Craft host or container.\n- Cause denial of service or establish persistence depending on deployment permissions.",
  "id": "GHSA-265m-7826-wjqm",
  "modified": "2026-08-06T20:45:00Z",
  "published": "2026-08-06T20:45:00Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/craftcms/cms/security/advisories/GHSA-265m-7826-wjqm"
    },
    {
      "type": "WEB",
      "url": "https://github.com/craftcms/cms/commit/353b5d676c88a854c9f6409ad83b837ca0c0e8da"
    },
    {
      "type": "WEB",
      "url": "https://github.com/craftcms/cms/commit/789789dc9e2a4e2f2562f51aaf879fb7757d8340"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/craftcms/cms"
    },
    {
      "type": "WEB",
      "url": "https://github.com/craftcms/cms/releases/tag/4.18.2"
    },
    {
      "type": "WEB",
      "url": "https://github.com/craftcms/cms/releases/tag/5.10.6"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Craft CMS: Authenticated RCE via `condition.config` JSON cleanse bypass"
}