XSS in Ci4-Cms-Erp Ci4ms
CVE-2026-39390
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 Google Maps iframe setting (cMap field) in compInfosPost() sanitizes input using strip_tags() with an <iframe> allowlist and regex-based removal of on\w+ event handlers. However, the srcdoc attribute is not an event handler and passes all filters. An attacker with admin settings access can inject an <iframe srcdoc="..."> payload with HTML-entity-encoded JavaScript that executes in the context of the parent page when rendered to unauthenticated frontend visitors. This vulnerability is fixed in 0.31.4.0.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.002 (13.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 14th percentile — 13.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000
Affected products
- Ci4-Cms-Erp Ci4ms — versions < 0.31.4.0
Weakness classification (CWE)
References
- github.com/ci4-cms-erp/ci4ms/security/advisories/GHSA-x3hr-cp7x-44r2 (Vendor Advisory)
Frequently asked questions
- What is CVE-2026-39390?
- CVE-2026-39390 is a medium-severity vulnerability in Ci4-Cms-Erp Ci4ms, classified under Cross-site Scripting. CVSS score: 5.5/10. Published 2026-04-08.
- How severe is CVE-2026-39390?
- Medium severity. CVSS v3 base score is 5.5 out of 10.