Headline
GHSA-52m2-vc4m-jj33: Twig may load a template outside a configured directory when using the filesystem loader
Description
When using the filesystem loader to load templates for which the name is a user input, it is possible to use the source or include statement to read arbitrary files from outside the templates directory when using a namespace like @somewhere/../some.file (in such a case, validation is bypassed).
Resolution
We fixed validation for such template names.
Even if the 1.x branch is not maintained anymore, a new version has been released.
Credits
We would like to thank Dariusz Tytko for reporting the issue and Fabien Potencier for fixing the issue.
Twig may load a template outside a configured directory when using the filesystem loader
High severity GitHub Reviewed Published Sep 30, 2022 in twigphp/Twig • Updated Sep 30, 2022
Package
composer twig/twig (Composer)
Affected versions
>= 1.0.0, < 1.44.7
>= 2.0.0, < 2.15.3
>= 3.0.0, < 3.4.3
Patched versions
1.44.7
2.15.3
3.4.3
Description
Description
When using the filesystem loader to load templates for which the name is a user input, it is possible to use the source or include statement to read arbitrary files from outside the templates directory when using a namespace like @somewhere/…/some.file (in such a case, validation is bypassed).
Resolution
We fixed validation for such template names.
Even if the 1.x branch is not maintained anymore, a new version has been released.
Credits
We would like to thank Dariusz Tytko for reporting the issue and Fabien Potencier for fixing the issue.
References
- GHSA-52m2-vc4m-jj33
- https://nvd.nist.gov/vuln/detail/CVE-2022-39261
- twigphp/Twig@35f3035
- https://github.com/FriendsOfPHP/security-advisories/blob/master/twig/twig/CVE-2022-39261.yaml
- https://symfony.com/blog/twig-security-release-possibility-to-load-a-template-outside-a-configured-directory-when-using-the-filesystem-loader
- https://www.drupal.org/sa-core-2022-016
fabpot published the maintainer security advisory
Sep 28, 2022
Severity
High
7.5
/ 10
CVSS base metrics
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Weaknesses
CWE-22
CVE ID
CVE-2022-39261
GHSA ID
GHSA-52m2-vc4m-jj33
Source code
twigphp/Twig
Checking history
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Twig is a template language for PHP. Versions 1.x prior to 1.44.7, 2.x prior to 2.15.3, and 3.x prior to 3.4.3 encounter an issue when the filesystem loader loads templates for which the name is a user input. It is possible to use the `source` or `include` statement to read arbitrary files from outside the templates' directory when using a namespace like `@somewhere/../some.file`. In such a case, validation is bypassed. Versions 1.44.7, 2.15.3, and 3.4.3 contain a fix for validation of such template names. There are no known workarounds aside from upgrading.