Twig is a template language for PHP. When using the ?? operator, output escaping was missing for the expression on the left side of the operator. This vulnerability is fixed in 3.19.0.

Twig is a template language for PHP. In a sandbox, an attacker can access attributes of Array-like objects as they were not checked by the security policy. They are now checked via the property policy and the `__isset()` method is now called after the security check. This is a BC break. This issue has been patched in versions 3.11.2 and 3.14.1. All users are advised to upgrade. There are no known workarounds for this issue.

Twig is a template language for PHP. In a sandbox, an attacker can call `__toString()` on an object even if the `__toString()` method is not allowed by the security policy when the object is part of an array or an argument list (arguments to a function or a filter for instance). This issue has been patched in versions 3.11.2 and 3.14.1. All users are advised to upgrade. There are no known workarounds for this issue.

Twig is a template language for PHP. Under some circumstances, the sandbox security checks are not run which allows user-contributed templates to bypass the sandbox restrictions. This vulnerability is fixed in 1.44.8, 2.16.1, and 3.14.0.

Symfony is a PHP framework for web and console applications and a set of reusable PHP components. Starting in versions 2.0.0, 5.0.0, and 6.0.0 and prior to versions 4.4.51, 5.4.31, and 6.3.8, some Twig filters in CodeExtension use `is_safe=html` but don't actually ensure their input is safe. As of versions 4.4.51, 5.4.31, and 6.3.8, Symfony now escapes the output of the affected filters.

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.

Twig is an open source template language for PHP. When in a sandbox mode, the `arrow` parameter of the `sort` filter must be a closure to avoid attackers being able to run arbitrary PHP functions. In affected versions this constraint was not properly enforced and could lead to code injection of arbitrary PHP code. Patched versions now disallow calling non Closure in the `sort` filter as is the case for some other filters. Users are advised to upgrade.

A sandbox information disclosure exists in Twig before 1.38.0 and 2.x before 2.7.0 because, under some circumstances, it is possible to call the __toString() method on an object even if not allowed by the security policy in place.

Twig before 2.4.4 allows Server-Side Template Injection (SSTI) via the search search_key parameter. NOTE: the vendor points out that Twig itself is not a web application and states that it is the responsibility of web applications using Twig to properly wrap input to it

perl-XML-Twig: The option to `expand_external_ents`, documented as controlling external entity expansion in XML::Twig does not work. External entities are always expanded, regardless of the option's setting.