CVE-2026-70552

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.

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://github.com/maxsite/cms
https://max-3000.com/page/maxsite-cms-109-6
https://www.vulncheck.com/advisories/maxsite-cms-unauthenticated-ajax-dispatcher-bypass-via-ajax-php

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-04 20:16

Updated : 2026-08-31 20:19

NVD link : CVE-2026-70552

Mitre link : CVE-2026-70552

CVE.ORG link : CVE-2026-70552

JSON object : View

Products Affected

No product.

CWE

CWE-306

Missing Authentication for Critical Function

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