CVE-2026-61511

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.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
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://karmainsecurity.com/KIS-2026-13
https://ssd-disclosure.com/vbulletin-runtime-template-runmaths-preauth-rce/
https://www.vulncheck.com/advisories/vbulletin-eval-injection-rce-via-vb5-template-runtime-php
http://seclists.org/fulldisclosure/2026/Aug/29

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-27 14:16

Updated : 2026-08-07 06:16

NVD link : CVE-2026-61511

Mitre link : CVE-2026-61511

CVE.ORG link : CVE-2026-61511

JSON object : View

Products Affected

No product.

CWE

CWE-95

Improper Neutralization of Directives in Dynamically Evaluated Code ('Eval Injection')

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