CVE-2025-71278: Xenforo

High severity, CVSS 8.8. EPSS: 0.3% chance of exploitation in the next 30 days.

XenForo before 2.3.5 allows OAuth2 client applications to request unauthorized scopes. This affects any customer using OAuth2 clients on any version of XenForo 2.3 prior to 2.3.5, potentially allowing client applications to gain access beyond their intended authorization level.

Affected products

• Xenforo Xenforo: from 2.3.0, before 2.3.5 (fixed in 2.3.5)

Published 2026-04-01. Last modified 2026-06-17.