The file download facility doesn't sufficiently sanitize file paths in certain situations. This may result in users gaining access to private files that they should not have access to. Some sites may require configuration changes following this security release. Review the release notes for your Drupal version if you have issues accessing private files after updating.

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's form API has a vulnerability where certain contributed or custom modules' forms may be vulnerable to improper input validation. This could allow an attacker to inject disallowed values or overwrite data. Affected forms are uncommon, but in certain cases an attacker could alter critical or sensitive data.

Cross-site Scripting (XSS) vulnerability in Drupal core's sanitization API fails to properly filter cross-site scripting under certain circumstances. This issue affects: Drupal Core 9.1.x versions prior to 9.1.7; 9.0.x versions prior to 9.0.12; 8.9.x versions prior to 8.9.14; 7.x versions prior to 7.80.

jQuery-UI is the official jQuery user interface library. Prior to version 1.13.0, accepting the value of the `of` option of the `.position()` util from untrusted sources may execute untrusted code. The issue is fixed in jQuery UI 1.13.0. Any string value passed to the `of` option is now treated as a CSS selector. A workaround is to not accept the value of the `of` option from untrusted sources.

jQuery-UI is the official jQuery user interface library. Prior to version 1.13.0, accepting the value of various `*Text` options of the Datepicker widget from untrusted sources may execute untrusted code. The issue is fixed in jQuery UI 1.13.0. The values passed to various `*Text` options are now always treated as pure text, not HTML. A workaround is to not accept the value of the `*Text` options from untrusted sources.

jQuery-UI is the official jQuery user interface library. Prior to version 1.13.0, accepting the value of the `altField` option of the Datepicker widget from untrusted sources may execute untrusted code. The issue is fixed in jQuery UI 1.13.0. Any string value passed to the `altField` option is now treated as a CSS selector. A workaround is to not accept the value of the `altField` option from untrusted sources.

Cross Site Request Forgery vulnerability in Drupal Core Form API does not properly handle certain form input from cross-site requests, which can lead to other vulnerabilities.

Open Redirect vulnerability in Drupal Core allows a user to be tricked into visiting a specially crafted link which would redirect them to an arbitrary external URL. This issue affects: Drupal Drupal Core 7 version 7.70 and prior versions.

Cross-site scripting vulnerability in Drupal Core. Drupal AJAX API does not disable JSONP by default, allowing for an XSS attack. This issue affects: Drupal Drupal Core 7.x versions prior to 7.73; 8.8.x versions prior to 8.8.10; 8.9.x versions prior to 8.9.6; 9.0.x versions prior to 9.0.6.

Tar.php in Archive_Tar through 1.4.11 allows write operations with Directory Traversal due to inadequate checking of symbolic links, a related issue to CVE-2020-28948.

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.

Archive_Tar through 1.4.10 has :// filename sanitization only to address phar attacks, and thus any other stream-wrapper attack (such as file:// to overwrite files) can still succeed.

Archive_Tar through 1.4.10 allows an unserialization attack because phar: is blocked but PHAR: is not blocked.

In jQuery versions greater than or equal to 1.2 and before 3.5.0, passing HTML from untrusted sources - even after sanitizing it - to one of jQuery's DOM manipulation methods (i.e. .html(), .append(), and others) may execute untrusted code. This problem is patched in jQuery 3.5.0.

In jQuery versions greater than or equal to 1.0.3 and before 3.5.0, passing HTML containing <option> elements from untrusted sources - even after sanitizing it - to one of jQuery's DOM manipulation methods (i.e. .html(), .append(), and others) may execute untrusted code. This problem is patched in jQuery 3.5.0.

The PharStreamWrapper (aka phar-stream-wrapper) package 2.x before 2.1.1 and 3.x before 3.1.1 for TYPO3 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.

jQuery before 3.4.0, as used in Drupal, Backdrop CMS, and other products, mishandles jQuery.extend(true, {}, ...) because of Object.prototype pollution. If an unsanitized source object contained an enumerable __proto__ property, it could extend the native Object.prototype.

In Drupal 7 versions prior to 7.65; Drupal 8.6 versions prior to 8.6.13;Drupal 8.5 versions prior to 8.5.14. Under certain circumstances the File module/subsystem allows a malicious user to upload a file that can trigger a cross-site scripting (XSS) vulnerability.

In Drupal Core versions 7.x prior to 7.62, 8.6.x prior to 8.6.6 and 8.5.x prior to 8.5.9; 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.