Vulnerability · Published Apr 8, 2026 · Assigned by GitHub_M

CVE-2026-39391CI4MS has Stored XSS via Unescaped Blacklist Note in Admin User List

Medium 4.8

In plain English

A medium-severity cross-site scripting in ci4ms from ci4-cms-erp. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 14% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)4.8Medium

Exploit odds (30 days)0.2%top 85.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

CI4MS is a CodeIgniter 4-based CMS skeleton that delivers a production-ready, modular architecture with RBAC authorization and theme support. Prior to 0.31.4.0, the blacklist (ban) note parameter in UserController::ajax_blackList_post() is stored in the database without sanitization and rendered into an HTML data-note attribute without escaping. An admin with blacklist privileges can inject arbitrary JavaScript that executes in the browser of any other admin who views the user management page. This vulnerability is fixed in 0.31.4.0.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Packagist	ci4-cms-erp/ci4ms	0.31.4.0	GHSA-7cm9-v848-cfh2

Affected products (as reported)

Vendor	Product	Versions
ci4-cms-erp	ci4ms	< 0.31.4.0

Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N

References

https://github.com/ci4-cms-erp/ci4ms/security/advisories/GHSA-7cm9-v848-cfh2 x_refsource_CONFIRM