Intel

AIKIDO-2026-424040

drupal/core is vulnerable to Improper Input Validation

Improper Input ValidationCVE-2026-55808 Published Yesterday

53

Medium Risk

This Affects:

PHPdrupal/core
0.0.0 - 10.5.11
Fixed in 10.5.12
10.6.0 - 10.6.10
Fixed in 10.6.11
11.0.0 - 11.2.13
Fixed in 11.2.14
11.3.0 - 11.3.11
Fixed in 11.3.12
Are you affected? Scan for Free

TL;DR

The JSON:API and REST modules validate uploaded image files by checking only the file extension, not the actual MIME type, allowing malicious users to upload non-image files that, depending on web-server configuration, may be served with their real MIME type—potentially leading to XSS or other unintended behavior.

Who does this affect?

You are affected if you are using a version that falls within the vulnerable range.

Background info

drupal/core is vulnerable to Improper Input Validation in versions 0.0.0 - 10.5.11, 10.6.0 - 10.6.10, 11.0.0 - 11.2.13 and 11.3.0 - 11.3.11.

How to fix this

Upgrade the drupal/core library to the patch version.