CVE-2026-66748
Medium
Elevated severity or exploit probability.
CVSS base
8.8
HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS — probability of exploitation (30 days)
1.1%
65.1th percentile
CISA KEV
Not listed
Weakness / dates
CWE-94
Published 2026-07-28 · modified 2026-07-31
Description
Camaleon CMS versions 2.1.1 through 2.9.1 contains an authenticated remote code execution vulnerability that allows users with custom_fields manage permission to execute arbitrary Ruby code by supplying a malicious expression through the select_eval custom field type. Attackers can store an attacker-controlled Ruby expression in the field options command parameter, which is evaluated via instance_eval within an ERB view whenever a post edit page is rendered, achieving server-side code execution with web server process privileges.
References
- https://enrik-m.github.io/posts/Camaleon-CMS-Vulnerabilties/
- https://github.com/owen2345/camaleon-cms/commit/158823668e2e5c3114a69b34cf1c96cb41533c5f
- https://github.com/owen2345/camaleon-cms/pull/1136
- https://github.com/owen2345/camaleon-cms/releases/tag/2.9.2
- https://github.com/theopaid/Camaleon-CMS---Authenticated-RCE-via-select_eval-Custom-Field
- https://tpaidakis.com/writeups/camaleon-cms-rce-select-eval/
- https://www.vulncheck.com/advisories/camaleon-cms-authenticated-rce-via-select-eval-custom-field
- https://github.com/theopaid/Camaleon-CMS---Authenticated-RCE-via-select_eval-Custom-Field