Package Instance

Drupal core contains a potential PHP Object Injection vulnerability that (if combined with another exploit) could lead to Artbitrary File Deletion. It is not directly exploitable.

This issue is mitigated by the fact that in order to be exploitable, a separate vulnerability must be present that allows an attacker to pass unsafe input to `unserialize()`. There are no such known exploits in Drupal core.

To help protect against this vulnerability, types have been added to properties in some of Drupal core's classes. If an application extends those classes, the same types may need to be specified on the subclass to avoid a `TypeError`.

This issue affects Drupal Core: from 8.0.0 before 10.2.11, from 10.3.0 before 10.3.9, from 11.0.0 before 11.0.8.

Drupal core contains a potential PHP Object Injection vulnerability that (if combined with another exploit) could lead to Remote Code Execution. It is not directly exploitable.

This issue is mitigated by the fact that in order for it to be exploitable, a separate vulnerability must be present to allow an attacker to pass unsafe input to `unserialize()`. There are no such known exploits in Drupal core.

To help protect against this potential vulnerability, types have been added to properties in some of Drupal core's classes. If an application extends those classes, the same types may need to be specified on the subclass to avoid a `TypeError`.

This issue affects Drupal Core: from 8.0.0 before 10.2.11, from 10.3.0 before 10.3.9, from 11.0.0 before 11.0.8.

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.

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.

Multiple vulnerabilities through filename manipulation in Archive_Tar
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. See: https://github.com/pear/Archive_Tar/issues/33

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.

Directory Traversal in Archive_Tar
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.

### :exclamation: Note: 
There was an [initial fix](https://github.com/pear/Archive_Tar/commit/cde460582ff389404b5b3ccb59374e9b389de916) for this vulnerability made in version `1.4.12`. That fix introduced a bug which was [fixed in 1.4.13](https://github.com/pear/Archive_Tar/pull/36). Therefore we have set the first-patched-version to `1.4.13` which the earliest working version that avoids this vulnerability.