Описание
Twig: Sandbox property and method bypass via object-destructuring assignment
Description
The object-destructuring assignment syntax introduced in Twig 3.24.0 generates a call to CoreExtension::getAttribute() with the $sandboxed argument hardcoded to false, regardless of whether a SandboxExtension is active. This permanently disables the sandbox's property and method policy checks for every destructuring expression.
ObjectDestructuringSetBinary::compile() emits:
Whereas GetAttrExpression::compile() correctly passes $env->hasExtension(SandboxExtension::class).
An attacker with write access to a sandboxed Twig template can read any public property or invoke any public getter on objects passed to the template engine, bypassing SecurityPolicy restrictions. The exploit requires only the {% do %} tag to be in allowedTags, which is a common configuration.
Resolution
The destructuring compiler now forwards the active sandbox flag to getAttribute() so property/method allowlists are enforced.
Credits
Twig would like to thank Anvil Secure in collaboration with Claude and Anthropic Research for reporting and fixing the issue.
Пакеты
twig/twig
>= 3.24.0, < 3.26.0
3.26.0
Связанные уязвимости
Twig is a template language for PHP. From 3.24.0 until 3.26.0, object-destructuring assignment compiles CoreExtension::getAttribute() with the sandbox argument hardcoded to false, disabling property and method policy checks and allowing an attacker with write access to a sandboxed Twig template to read public properties or invoke public getters on objects passed to the template engine. This issue is fixed in version 3.26.0.
Twig is a template language for PHP. From 3.24.0 until 3.26.0, object-destructuring assignment compiles CoreExtension::getAttribute() with the sandbox argument hardcoded to false, disabling property and method policy checks and allowing an attacker with write access to a sandboxed Twig template to read public properties or invoke public getters on objects passed to the template engine. This issue is fixed in version 3.26.0.
Twig is a template language for PHP. From 3.24.0 until 3.26.0, object- ...