CVE-2026-66748 Camaleon CMS 2.1.1 - 2.9.1 Authenticated RCE via select_eval Custom Field
Authenticated attackers with custom field permissions can execute arbitrary Ruby code via malicious expressions in select_eval fields, leading to server compromise.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-66748?
CVE-2026-66748 is a high-severity code injection vulnerability in owen2345 camaleon-cms, published on 28 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official 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.
Weakness: CWE-94
Which versions are affected by CVE-2026-66748?
How do I fix CVE-2026-66748?
No fix has been published for CVE-2026-66748 yet. Limit exposure of the affected software until one is available.
Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.
Is CVE-2026-66748 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-66748 exists.
Public exploit code: 1 proofs of concept on GitHub.
Sources
Also known as GHSA-7xm9-634w-f5r7.