CVE-2026-87930 (GCVE-0-2026-87930)

Vulnerability from cvelistv5 – Published: 2026-09-09 16:45 – Updated: 2026-09-24 14:21 X_Open Source Unsupported When Assigned
VLAI
Title
MaxSite CMS through 109.6 PHP Object Injection via ci_session
Summary
MaxSite CMS through 109.6 passes the ci_session cookie to unserialize() without class restrictions, allowing unauthenticated attackers to inject PHP objects. Attackers can forge valid session cookies using the hardcoded encryption key to trigger magic methods and corrupt application state or achieve code execution if gadget classes exist.
Severity
9.2 (Critical)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
8.1 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-09 17:22 UTC
CWE
  • CWE-502 - Deserialization of Untrusted Data
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 7156 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
MaxSite MaxSite CMS Affected: 0.78 , ≤ 109.6 (custom)
    cpe:2.3:a:max-3000:maxsite_cms:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-09-09 00:00
Credits
EVIL0RD
Show details on NVD website
To clipboard 

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}



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