Drupal Improper Limitation of a Pathname to a Restricted Directory (Path Traversal) Vulnerability - CVE-2022-39261
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 templates39 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.