Vulnerability identifier: #VU57966

Vulnerability risk: Medium

CVSSv3.1: 4.7 [CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: N/A

CWE-ID: CWE-434

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
BookStack
Client/Desktop applications / Other client software

Vendor: Dan Brown

Description

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.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

BookStack: 21.04 - 21.10.2

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External links
http://github.com/BookStackApp/BookStack/releases/tag/v21.10.3

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.