{
  "affected": [
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "twig/twig"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.15.0"
            },
            {
              "fixed": "3.26.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-46640"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-94"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-21T21:31:08Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "### Description\n\nThe `obj.(expr)` dynamic-attribute syntax (added in 3.15.0 as the replacement for the deprecated `attribute()` function) lets the attribute be an arbitrary expression. When the receiver is `_self` (or any `{% import %}` alias) and the parenthesised expression is a string literal, `DotExpressionParser` short-circuits to the macro-call path and concatenates the attacker-controlled string into a `MacroReferenceExpression` name with no identifier validation. `MacroReferenceExpression::compile()` then emits that name raw into the generated PHP source.\n\nAn attacker who can supply template source can inject arbitrary PHP into the compiled template and execute it at template-load time, before `checkSecurity()` is ever called. This is a complete bypass of `SandboxExtension`, including a globally-enabled sandbox with an empty `SecurityPolicy` allowlist.\n\n### Resolution\n\nThe parser now validates that the dynamic attribute resolves to a valid macro identifier before routing through `MacroReferenceExpression`, and the macro-reference compiler emits the name through a properly escaped path.\n\n### Credits\n\nTwig would like to thank Claude Mythos Preview (via Project Glasswing) for reporting the issue and providing the fix.",
  "id": "GHSA-45vw-wh46-2vx8",
  "modified": "2026-06-05T20:33:13Z",
  "published": "2026-05-21T21:31:08Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/twigphp/Twig/security/advisories/GHSA-45vw-wh46-2vx8"
    },
    {
      "type": "WEB",
      "url": "https://github.com/FriendsOfPHP/security-advisories/blob/master/twig/twig/CVE-2026-46640.yaml"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/twigphp/Twig"
    },
    {
      "type": "WEB",
      "url": "https://github.com/vladko312/extras/blob/main/CVE-2026-46640.py"
    },
    {
      "type": "WEB",
      "url": "https://symfony.com/cve-2026-46640"
    }
  ],
  "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": "Twig: Arbitrary PHP code execution via `_self.(\u003cstring\u003e)` macro-reference compilation"
}