Security Advisories

Backdrop CMS allows the upload of entire-site configuration archives through the user interface or command-line. Backdrop CMS does not sufficiently check uploaded archives for invalid data, allowing non-configuration scripts to potentially be uploaded to the server.

This attack is mitigated by the attacker needing the "Synchronize, import, and export configuration" permission, a permission that only trusted administrators should be given. Other preventative measures in Backdrop CMS prevent the execution of PHP scripts, so another server-side scripting language must be accessible on the server to execute code.

Backdrop CMS doesn't sufficiently filter output when displaying certain block labels created by administrators. An attacker could potentially craft a specialized label, then have an administrator execute scripting when administering a layout.

This issue is mitigated by the attacker requiring permission to create custom blocks on the site, which is typically an administrative permission.

Some menu links within the administration bar may be crafted to execute JavaScript when the administrator is logged in and uses the search functionality.

This issue is mitigated by the attacker needing permissions to create administrative menu links, such as by creating a content type or layout. Such permissions are usually restricted to trusted or administrative users.

This module allows you to attach tabular data to any fieldable entity like a node, user, or term.

Access bypass

There's no access check for users with the "Export Tablefield Data as CSV" permission. They are able to export data from unpublished nodes or otherwise inaccessible entities.

This vulnerability is mitigated by the fact that an attacker must have a role with the permission 'Export Tablefield Data as CSV'.

The jQuery project released version 3.4.0, and as part of that, disclosed a security vulnerability that affects all prior versions. As described in their release notes:

jQuery 3.4.0 includes a fix for some unintended behavior when using jQuery.extend(true, {}, ...). If an unsanitized source object contained an enumerable __proto__ property, it could extend the native Object.prototype. This fix is included in jQuery 3.4.0, but patch diffs exist to patch previous jQuery versions.

It's possible that this vulnerability is exploitable with some Backdrop modules. As a precaution, this Backdrop security release backports the fix to jQuery.extend(), without making any other changes to the jQuery version 1.12.4 that is included in Backdrop core.

The tablefield module allows you to attach tabular data to an entity.

The module doesn't sufficiently determine that the data being unserialized is the contents of a tablefield when users request a CSV export, which could lead to Remote Code Execution via Object Injection.

This vulnerability is mitigated by the fact that an attacker must have a role with the permission 'export tablefield', and be able to insert a payload into an entity's field.

This module provides a standardized solution for building API's so that external clients can communicate with Backdrop.

The Services module has an access bypass vulnerability in its "attach_file" resource that allows users who have access to create or update pieces of content that include file fields to arbitrarily reference files they do not have access to, which can expose private files.

This vulnerability is mitigated by the fact that an attacker must have a role with permission to create or edit a piece of content.

This module enables you to add a button that hovers in the bottom of your screen and allows users to smoothly scroll up the page using jQuery.

The module doesn't sufficiently sanitize the code that gets printed on pages leading to a Cross Site Scripting (XSS) issue.

This vulnerability is mitigated by the fact that an attacker must have a role with the permission "access backtotop settings".

Under certain circumstances the File module/subsystem allows a malicious user to upload a file that can trigger a cross-site scripting (XSS) vulnerability.

The Views module included in Backdrop core doesn't sufficiently sanitize certain field types, leading to a Cross Site Scripting (XSS) vulnerability.

This vulnerability is mitigated by the fact that a view must display a field with the format "Full data (serialized)" and an attacker must have the ability to store malicious markup in that field.

Additional information

Note: Backdrop issues individual security advisories for separate vulnerabilities included in a release, rather than lumping "multiple vulnerabilities" into a single advisory. All advisories released today for Backdrop core:

• BACKDROP-SA-CORE-2019-005
• BACKDROP-SA-CORE-2019-006
• BACKDROP-SA-CORE-2019-007