Date: 
Wednesday, Mar 19th, 2025
Advisory ID: 
BACKDROP-SA-CORE-2025-004
Security risk: 
Less Critical
Vulnerability: 
Cross Site Scripting
Versions affected: 
  • Backdrop Core 1.30.x versions prior to 1.30.2
  • Backdrop Core 1.29.x versions prior to 1.29.5

Backdrop versions 1.28 and prior do not receive security coverage.

Description: 

Backdrop core Link field attributes may not be sufficiently sanitized in specialized scenarios, which can lead to a Cross Site Scripting vulnerability (XSS).

This vulnerability is not directly exploitable within core itself, nor are there any contributed modules that appear to exhibit the behavior. This is a security hardening to prevent such attacks in the future. This problem has not been reproducible without a specialized module. 

Sites are not affected if they are not extending the Link field module in ways that provide the ability to input additional link attributes.

Solution: 

Upgrade your site to the most recent version of Backdrop core. Download available on the Backdrop CMS 1.30.2 release page. See the update instructions, if needed.

Fixed By: 
Coordinated By: 

Security email list

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