CouchCMS contains a privilege escalation vulnerability that allows authenticated Admin-level users to create SuperAdmin accounts by tampering with the f_k_levels_list parameter in user creation requests. Attackers can modify the parameter value from 4 to 10 in the HTTP request body to bypass authorization validation and gain full application control, circumventing restrictions on SuperAdmin account creation and privilege assignment.
https://www.vulncheck.com/advisories/couchcms-privilege-escalation-via-f-k-levels-list-parameter
https://gist.github.com/thepiyushkumarshukla/477e2d2bbbe8cc3ec0d640c50f0cf9e1
Published: 2026-04-10
Updated: 2026-04-10
Base Score: 8.3
Vector: CVSS2#AV:N/AC:L/Au:M/C:C/I:C/A:C
Severity: High
Base Score: 7.2
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Severity: High
Base Score: 8.6
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Severity: High