MaxSite CMS 109.5 and earlier — CVE-2026-70552 (Critical)

Summary

MaxSite CMS 109.5 and earlier contains an authentication bypass vulnerability in the AJAX dispatcher that allows unauthenticated attackers to access admin-gated endpoints by supplying any X-Requested-With header and requesting a base64-encoded path resolving to any *-ajax.php file in the codebase. Attackers can exploit this dispatcher bypass to reach privileged plugin endpoints without credentials, enabling actions such as manipulating poll states and vote counts, and amplifying the impact of any dangerous operation performed by admin-only ajax files across the plugin tree.

Why it matters

This CVE carries a CRITICAL severity rating (CVSS 9.8) in MaxSite CMS 109.5 and earlier. Patch or mitigate promptly.

Operator check

Review CVE-2026-70552 in your asset inventory. Apply patches per vendor guidance and verify CMS 109.5 and earlier is not exposed. CVSS score: 9.8.

Sources