GHSA-45vw-wh46-2vx8
Suggest an improvement- Source
- https://github.com/advisories/GHSA-45vw-wh46-2vx8
- Import Source
- https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/05/GHSA-45vw-wh46-2vx8/GHSA-45vw-wh46-2vx8.json
- JSON Data
- https://api.osv.dev/v1/vulns/GHSA-45vw-wh46-2vx8
- Aliases
-
- CVE-2026-46640
- Related
- Published
- 2026-05-21T21:31:08Z
- Modified
- 2026-05-23T18:29:18.836778321Z
- Severity
-
- 8.7 (High) CVSS_V4 - 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 CVSS Calculator
- Summary
- Twig: Arbitrary PHP code execution via `_self.(<string>)` macro-reference compilation
- Details
-
Description
The
obj.(expr)dynamic-attribute syntax (added in 3.15.0 as the replacement for the deprecatedattribute()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,DotExpressionParsershort-circuits to the macro-call path and concatenates the attacker-controlled string into aMacroReferenceExpressionname with no identifier validation.MacroReferenceExpression::compile()then emits that name raw into the generated PHP source.An 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 ofSandboxExtension, including a globally-enabled sandbox with an emptySecurityPolicyallowlist.Resolution
The 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.Credits
Twig would like to thank Claude Mythos Preview (via Project Glasswing) for reporting the issue and providing the fix.
- Database specific
{ "cwe_ids": [ "CWE-94" ], "github_reviewed": true, "github_reviewed_at": "2026-05-21T21:31:08Z", "nvd_published_at": null, "severity": "HIGH" }- References
Affected packages
Packagist / twig/twig
Package
- Name
- twig/twig
- Purl
- pkg:composer/twig%2Ftwig