Security advisories for Drupal core

The Layout Builder module doesn't sufficiently sanitize block labels in certain scenarios, which can lead to a cross-site scripting (XSS) vulnerability.

This is mitigated by the fact that both the attacker and the targeted user need to be using the Layout Builder editing interface.

The Image module allows you to define and configure image fields.

The module doesn't sufficiently check access to image style derivatives when those files are served via a file stream other than private://.

This vulnerability is mitigated by the fact that Drupal must be configured to use a contributed (non-core) file scheme to serve private derived images.

The Media module comes with support for oEmbed. The oEmbed specification contains two discovery mechanisms, via providers.json and via URL discovery.

The URL discovery code could be leveraged to trick Drupal into making server-side requests to any URL.

Drupal core contains a chain of methods that could be exploitable when an insecure deserialization vulnerability exists on the site. This so-called "gadget chain" presents no direct threat, but is a vector that can be used to achieve remote code execution or SQL injection if the application deserializes untrusted data due to another vulnerability.

This issue is not directly exploitable.

Drupal core includes a database abstraction API to ensure that queries executed against the database are sanitized to prevent SQL injection attacks.

A vulnerability in this API allows an attacker to send specially crafted requests, resulting in arbitrary SQL injection for sites using PostgreSQL databases. This can lead to information disclosure, and in some cases privilege escalation, remote code execution, or other attacks.

This vulnerability can be exploited by anonymous users.

Drupal core contains a chain of methods that could be exploitable when an insecure deserialization vulnerability exists on the site. This so-called "gadget chain" presents no direct threat, but is a vector that can be used to achieve remote code execution or SQL injection if the application deserializes untrusted data due to another vulnerability.

This issue is not directly exploitable.

The core system module handles downloads of private and temporary files. Contrib modules can define additional kinds of files (schemes) that may also be handled by the system module.

In some cases, files may be served with the HTTP header Cache-Control: public when they should be uncacheable. This can lead to some users getting cached versions of files with information they should not be able to access. For example, files may be cached by Varnish or a CDN.

Drupal core contains a chain of methods that is exploitable when an insecure deserialization vulnerability exists on the site. This so-called "gadget chain" presents no direct threat, but is a vector that can be used to achieve remote code execution if the application deserializes untrusted data due to another vulnerability.

It is not directly exploitable.

Drupal core Link field attributes are not sufficiently sanitized, which can lead to a Cross Site Scripting vulnerability (XSS).

This vulnerability is mitigated by that fact that an attacker would need to have the ability to add specific attributes to a Link field, which typically requires edit access via core web services, or a contrib or custom module.

Sites with the Link module disabled or that do not use any link fields are not affected.

Bulk operations allow authorized users to modify several nodes at once from the Content page (/admin/content). A site builder can also add bulk operations to other pages using Views.

A bug in the core Actions system allows some users to modify some fields using bulk actions that they do not have permission to modify on individual nodes.

This vulnerability is mitigated by the fact that an attacker must have permission to access /admin/content or other, custom views and to edit nodes.

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.

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.

Drupal's uniqueness checking for certain user fields is inconsistent depending on the database engine and its collation.

As a result, a user may be able to register with the same email address as another user.

This may lead to data integrity issues.

Under certain uncommon site configurations, a bug in the CKEditor 5 module can cause some image uploads to move the entire webroot to a different location on the file system. This could be exploited by a malicious user to take down a site.

The issue is mitigated by the fact that several non-default site configurations must exist simultaneously for this to occur.

In certain scenarios, Drupal's JSON:API module will output error backtraces. With some configurations, this may cause sensitive information to be cached and made available to anonymous users, leading to privilege escalation.

This vulnerability only affects sites with the JSON:API module enabled, and can be mitigated by uninstalling JSON:API.

The core REST and contributed GraphQL modules are not affected.

Drupal core provides a page that outputs the markup from phpinfo() to assist with diagnosing PHP configuration.

If an attacker was able to achieve an XSS exploit against a privileged user, they may be able to use the phpinfo page to access sensitive information that could be used to escalate the attack.

This vulnerability is mitigated by the fact that a successful XSS exploit is required in order to exploit it.

The Media module does not properly check entity access in some circumstances. This may result in users seeing thumbnails of media items they do not have access to, including for private files.

This release was coordinated with SA-CONTRIB-2023-010.

This advisory is not covered by Drupal Steward.

Drupal uses the Twig third-party library for content templating and sanitization. Twig has released a security update that affects Drupal. Twig has rated the vulnerability as high severity.

Drupal core's code extending Twig has also been updated to mitigate a related vulnerability.

Updated 2022-07-20 19:45 UTC to indicate that this only affects Apache web servers.

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).

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.

Drupal uses the third-party Guzzle library for handling HTTP requests and responses to external services. Guzzle has released a security update which does not affect Drupal core, but may affect some contributed projects or custom code on Drupal sites.

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.

We do not know of affected forms within core itself, but contributed and custom project forms could be affected. Installing this update will fix those forms.

This advisory is not covered by Drupal Steward.

The Drupal project uses the CKEditor library for WYSIWYG editing. CKEditor has released a security update that impacts Drupal.

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.

This advisory is not covered by Drupal Steward.