A remote PHP code execution vulnerability exists in InstantCMS version 1.6 and earlier due to unsafe use of eval() within the search view handler. Specifically, user-supplied input passed via the look parameter is concatenated into a PHP expression and executed without proper sanitation. A remote attacker can exploit this flaw by sending a crafted HTTP GET request with a base64-encoded payload in the Cmd header, resulting in arbitrary PHP code execution within the context of the web server.
Published: 2025-08-01
Updated: 2025-10-09
Base Score: 10
Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C
Severity: Critical
Base Score: 9.8
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity: Critical
Base Score: 9.3
Vector: 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
Severity: Critical
EPSS: 0.01894