Drupal core - Moderately critical - Improper validation - SA-CORE-2026-009

Drupal core - Moderately critical - Improper validation - SA-CORE-2026-009

https://www.drupal.org/security/rss.xml / Wed, 06/17/2026 - 20:45
Project: 
Drupal core
Date: 
2026-June-02
Security risk: 
Moderately critical 11 ∕ 25 AC:Complex/A:User/CI:Some/II:Some/E:Theoretical/TD:Uncommon
Vulnerability: 
Improper validation
Affected versions: 
<10.5.12 || >=10.6.0 <10.6.11 || >=11.2.0 <11.2.14 || >=11.3.0 <11.3.12 || 11.0.* || 11.1.*
CVE IDs: 
CVE-2026-55808
Description: 

The JSON:API and REST modules allow you to upload image files to image fields.

The validation rules check the file extension of the uploaded file but not the file MIME type. This may allow a malicious user to upload a file that is not an image.

Certain web-server configurations may serve the uploaded file with its actual MIME type rather than an image type. This may lead to cross-site scripting (XSS) or other unexpected behavior.

Solution: 

Install the latest version:

Drupal 11

Drupal 10

Drupal 11.1.x, Drupal 11.0.x, Drupal 10.4.x, and below are end-of-life and do not receive security coverage. (Drupal 8 and Drupal 9 have both reached end-of-life.)

Reported By: 
Fixed By: 
Coordinated By: 

About

Kenya Education Network CERT(KENET-CERT) is a Cybersecurity Emergency Response Team and Co-ordination Center operated by the National Research and Education Network of Kenya. KENET-CERT coordination center promotes awareness on cybersecurity incidences as well as coordinates and assists member institutions in responding effectively to cyber security threats and incidences. KENET-CERT works closely with Kenya's National CIRT coordination center (CIRT/CC) as a sector CIRT for the academic institutions. KENET promotes use of ICT in Teaching, Learning and Research in Higher Education Institutions in Kenya. KENET aims to interconnect all the Universities, Tertiary and Research Institutions in Kenya by setting up a cost effective and sustainable private network with high speed access to the global Internet. KENET also facilitates electronic communication among students and faculties in member institutions, share learning and teaching resources by collaboration in Research and Development of Educational content.