Package Instance

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.

Improper Input Validation
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.

Improper Access Control
Under certain circumstances, the Drupal core form API evaluates form element access incorrectly. This may lead to a user being able to alter data they should not have access to. No forms provided by Drupal core are known to be vulnerable. However, forms added through contributed or custom modules or themes may be affected.

Drupal core Multiple vulnerabilities due to the use of the third-party library Archive_Tar
The Drupal project uses the third-party library [Archive_Tar](https://pear.php.net/package/Archive_Tar/), which has released a security improvement that is needed to protect some Drupal configurations.

Multiple vulnerabilities are possible if Drupal is configured to allow .tar, .tar.gz, .bz2 or .tlz file uploads and processes them.

The latest versions of Drupal update Archive_Tar to 1.4.9 to mitigate the file processing vulnerabilities.

Drupal core Cross-site Scripting (XSS) vulnerability
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.

Drupal core uses a vulnerable Third-party library CKEditor
The Drupal project uses the third-party library [CKEditor](https://github.com/ckeditor/ckeditor4), which has released a [security improvement](https://ckeditor.com/blog/CKEditor-4.14-with-Paste-from-LibreOffice-released/#security-issues-fixed) that is needed to protect some Drupal configurations.

Vulnerabilities are possible if Drupal is configured to use the WYSIWYG CKEditor for your site's users. An attacker that can create or edit content may be able to exploit this Cross Site Scripting (XSS) vulnerability to target users with access to the WYSIWYG CKEditor, and this may include site admins with privileged access.

The latest versions of Drupal update CKEditor to 4.14 to mitigate the vulnerabilities.

Unrestricted Upload of File with Dangerous Type
Drupal core sanitizes filenames with dangerous extensions upon upload (reference: SA-CORE-2020-012) and strips leading and trailing dots from filenames to prevent uploading server configuration files (reference: SA-CORE-2019-010). However, the protections for these two vulnerabilities previously does not work correctly together. As a result, if the site were configured to allow the upload of files with an htaccess extension, these files' filenames would not be properly sanitized. This could allow bypassing the protections provided by Drupal core's default .htaccess files and possible remote code execution on Apache web servers. This issue is mitigated by the fact that it requires a field administrator to explicitly configure a file field to allow htaccess as an extension (a restricted permission), or a contributed module or custom code that overrides allowed file uploads.

Drupal core Cross-site Scripting (XSS) vulnerability in ckeditor
Cross-site Scripting (XSS) vulnerability in ckeditor of Drupal Core allows attacker to inject XSS. This issue affects: Drupal Core 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.

Lack of domain validation in Druple core
The Media oEmbed iframe route does not properly validate the iframe domain setting, which allows embeds to be displayed in the context of the primary domain. Under certain circumstances, this could lead to cross-site scripting, leaked cookies, or other vulnerabilities.