CVE-2026-87929

Vulncheck · Published September 9, 2026

9.8

CVSS v3.1

CRITICAL

Description

MaxSite CMS through 109.6 ships with a hardcoded session encryption key in application/config/config.php that is never changed during installation, allowing unauthenticated attackers to forge administrator session cookies. Attackers can mint a malicious ci_session cookie with administrator privileges by computing an HMAC-SHA1 using the publicly known encryption key, bypassing authentication checks in is_login() and mso_check_allow() functions.

Affected Products

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H