CVE-2026-70552: critical vulnerability in MaxSite CMS
MaxSite CMS 109.5 Unauthenticated AJAX Dispatcher Bypass via ajax.php
Published · Updated
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28Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 9.3epss 0.8%
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:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Affected products
MaxSite · MaxSite CMSRelated CVEs — MaxSite CMS
In the same product, most dangerous first.
CVE-2026-70553CRITICALMaxSite CMS Unauthenticated RCE via Install EndpointEPSS 1.3%CVE-2026-70554CRITICALMaxSite CMS Unauthenticated PHP Object Injection via maxsite_comuser CookieEPSS 1.2%CVE-2026-87930CRITICALMaxSite CMS through 109.6 PHP Object Injection via ci_sessionEPSS 0.6%CVE-2026-87927HIGHMaxSite CMS through 109.6 Local File Inclusion via ajax dispatcherEPSS 0.6%CVE-2026-87929CRITICALMaxSite CMS through 109.6 Authentication Bypass via Hardcoded Encryption KeyEPSS 0.5%CVE-2026-87928MEDIUMMaxSite CMS 0.94 through 109.6 HTML Upload XSS via admin_pageEPSS 0.3%