#VU57966 Dangerous file upload in BookStack

Vulnerability identifier: #VU57966

Vulnerability risk: Medium

CVSSv4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green

CVE-ID: N/A

CWE-ID: CWE-434

Exploitation vector: Remote access

Exploit availability: No public exploit available

Vulnerable software:
BookStack

Software vendor:
Dan Brown

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 processing HTML attachments. A remote attacker can upload an HTML file to the server and perform phishing attacks.

Install updates from vendor's website.

• https://github.com/BookStackApp/BookStack/releases/tag/v21.10.3