SB2025011318 - Multiple vulnerabilities in Backdrop CMS

Description

This security bulletin contains information about 2 secuirty vulnerabilities.

1) Cross-site scripting (CVE-ID: N/A)

The disclosed vulnerability allows a remote user to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied data when handling SVG images. A remote user can upload a specially crafted SVG image and execute arbitrary HTML and script code in user's browser in context of vulnerable website.

Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.

2) Cross-site scripting (CVE-ID: N/A)

The disclosed vulnerability allows a remote user to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied data when handling long content with the CKEditor 5 rich text editor module. A remote user can inject specially crafted content, trick the website administrator into opening the specially crafted content with the CKEditor 5 module and execute arbitrary HTML and script code in user's browser in context of vulnerable website.

Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.

Remediation

Install update from vendor's website.

References

• https://backdropcms.org/security/backdrop-sa-core-2025-002
• https://backdropcms.org/security/backdrop-sa-core-2025-001