CVE-2026-87930

MaxSite CMS through 109.6 PHP Object Injection via ci_session

Published: Sep 9, 2026Updated: Sep 9, 2026 Sources: CVE List NVDCWE-502

8.1HIGH

Description

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:HAttack Complexity

High

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:HConfidentiality

High

I:HIntegrity

High

A:HAvailability

High

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Weaknesses

CWE-502

Affected Products

MaxSite

commercialaka maxsite cms

MaxSite CMSOn-prem

Web & CMS Plugins / cms-core

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

3 techniques

Execution

Initial Access

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References

https://github.com/maxsite/cms

github.com

https://github.com/EviL0rd/maxsite-cve6/blob/main/2026.09.08-maxsite-cms-unsafe-unserialize-object-injection.md

github.com

https://github.com/maxsite/cms/blob/2ca0a0c7d1d71106a25dbb0f2aedaaefbf12802c/system/libraries/Session.php#L670-L680

github.com

and 4 more references View all →

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