Description
vBulletin 5.x through 5.7.5 and 6.x through 6.2.1 contains an eval injection vulnerability in the vB5_Template_Runtime::runMaths() method within the template runtime that allows unauthenticated remote attackers to execute arbitrary PHP code by supplying crafted input through the pagenav[pagenumber] parameter. Attackers can exploit the insufficiently restrictive regex filter by using phpfuck-style encoding with permitted characters to inject and execute arbitrary PHP code via the unauthenticated ajax/render template route without any authentication.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
vBulletin vBulletin
Default version status: affected
5.0.0 to ≤ 5.7.5affected6.0.0 to ≤ 6.2.1affected6.2.2unaffected
References
- https://karmainsecurity.com/KIS-2026-13 ↗
- https://ssd-disclosure.com/vbulletin-runtime-template-runmaths-preauth-rce/ ↗
- https://forum.vbulletin.com/forum/vbulletin-announcements/vbulletin-announcements_aa/4509358-security-patch-released-for-vbulletin-6-2-1-6-2-0-and-6-1-6 ↗
- https://forum.vbulletin.com/forum/vbulletin-announcements/vbulletin-announcements_aa/4509404-vbulletin-6-2-2-is-available ↗
- https://www.vulncheck.com/advisories/vbulletin-eval-injection-rce-via-vb5-template-runtime-php ↗
- http://seclists.org/fulldisclosure/2026/Aug/29 ↗