CVE-2008-4930: Mybb

Medium severity, CVSS 5.0. EPSS: 1.2% chance of exploitation in the next 30 days.

MyBB (aka MyBulletinBoard) 1.4.2 does not properly handle an uploaded file with a nonstandard file type that contains HTML sequences, which allows remote attackers to cause that file to be processed as HTML by Internet Explorer's content inspection, aka "Incomplete protection against MIME-sniffing." NOTE: this could be leveraged for XSS and other attacks.

Affected products

• Mybb Mybb: version 1.4.2 only

Published 2008-11-04. Last modified 2026-06-16.