Package Instance

Moderately critical - Third-party libraries - SA-CORE-2019-007
The `PharStreamWrapper` (aka `phar-stream-wrapper`) package does not prevent directory traversal, which allows attackers to bypass a deserialization protection mechanism, as demonstrated by a `phar:///path/bad.phar/../good.phar` URL.

Improper Input Validation
A remote code execution vulnerability exists in PHP's built-in phar stream wrapper when performing file operations on an untrusted `phar://` URI. Some Drupal code (core, contrib, and custom) may be performing file operations on insufficiently validated user input, thereby being exposed to this vulnerability. This vulnerability is mitigated by the fact that such code paths typically require access to an administrative permission or an atypical configuration.

Drupal Core Insufficient Contextual Links validation leads to Remote Code Execution
The Contextual Links module doesn't sufficiently validate the requested contextual links.
This vulnerability is mitigated by the fact that an attacker must have a role with the permission "access contextual links".

Cross-site Scripting
In Symfony, validation messages are not escaped, which can lead to XSS when user input is included.

Improper access control
In some situations, the Image module does not correctly check access to image files not stored in the standard public files directory when generating derivative images using the image styles system. Access to a non-public file is checked only if it is stored in the "private" file system. However, some contributed modules provide additional file systems, or schemes, which may lead to this vulnerability. This vulnerability is mitigated by the fact that it only applies when the site sets (Drupal 9) $config['image.settings']['allow_insecure_derivatives'] or (Drupal 7) $conf['image_allow_insecure_derivatives'] to TRUE. The recommended and default setting is FALSE, and Drupal core does not provide a way to change that in the admin UI. Some sites may require configuration changes following this security release. Review the release notes for your Drupal version if you have issues accessing files or image styles after updating.

Drupal core Unrestricted Upload of File with Dangerous Type
Drupal core does not properly sanitize certain filenames on uploaded files, which can lead to files being interpreted as the incorrect extension and served as the wrong MIME type or executed as PHP for certain hosting configurations. This issue affects: Drupal Drupal Core 9.0 versions prior to 9.0.8, 8.9 versions prior to 8.9.9, 8.8 versions prior to 8.8.11, and 7 versions prior to 7.74.