Authenticated Ruby code execution via unsandboxed instance_eval
Published Jul 28, 2026 · Updated Jul 28, 2026
Code injection in Camaleon CMS 2.1.1 through 2.9.1 allows remote authenticated users to execute arbitrary Ruby code. The select_eval ERB partial passes the stored field.options command value to instance_eval without sandboxing or a code allowlist whenever a post edit form renders. An account with the custom_fields manage permission, commonly assigned to editor roles, can persist code that runs with the Rails web server process privileges on each affected edit-page render.
Summary
What happened
Code injection in Camaleon CMS 2.1.1 through 2.9.1 allows remote authenticated users to execute arbitrary Ruby code. The select_eval ERB partial passes the stored field.options command value to instance_eval without sandboxing or a code allowlist whenever a post edit form renders. An account with the custom_fields manage permission, commonly assigned to editor roles, can persist code that runs with the Rails web server process privileges on each affected edit-page render.
The record
- CVE
- CVE-2026-66748
- Published
- Jul 28, 2026
- Updated
- Jul 28, 2026
- Vendor
- Camaleon CMS
- Product
- Camaleon CMS
- Classifications
- CWE-94, T1059
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 28, 2026CVE publishedPublication date reported by the CVE source.
- Jul 28, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=2.1.1 <=2.9.1
- Affected versionversion=2.9.2
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- CVE-2026-66748 authenticated select_eval RCE proof of conceptfunctional · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo