CVE-2026-107249
Critical
Description
The Block AJAX module enables you to load blocks asynchronously via Ajax. The module doesn't sufficiently validate user-supplied data which is used to construct a block. In the worst case scenario, this can lead to PHP Object Injection and Remote Code Execution. The vulnerability is mitigated by the fact that it only affects sites that have Layout Builder enabled (or another block plugin that handles the data this module passes to it in a potentially unsafe way). Please see the release notes for details of potentially breaking changes.
SeverityCritical
CVSS9.8
Exploit probability—
ProductDrupal/block Ajax
PublishedOct 7, 2026
First seenOct 7, 2026
Weakness typeCWE-915CWE-915
How to fix
Update
- drupal/block_ajax3.0.2 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| drupal/block_ajaxPackagist:https://packages.drupal.org/8 | v < 3.0.2 | 3.0.2 |
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