SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-34558

Multiple input fields accept attacker-controlled JavaScript payloads that are stored server-side without sanitization or output encoding.

CRITICAL 9.0EPSS 0.31%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.31%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

CI4MS is a CodeIgniter 4-based CMS skeleton that delivers a production-ready, modular architecture with RBAC authorization and theme support. Prior to version 0.31.0.0, the application fails to properly sanitize user-controlled input within the Methods Management functionality when creating or managing application methods/pages. Multiple input fields accept attacker-controlled JavaScript payloads that are stored server-side without sanitization or output encoding. These stored values are later rendered directly into administrative interfaces and global navigation components without proper encoding, resulting in Stored DOM-Based Cross-Site Scripting (XSS). This issue has been patched in version 0.31.0.0.

CVSS 3.1
9.0 CRITICALCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H
EPSS
0.31% probability · 23th percentile
CISA KEV
Not listed
Weakness
CWE-79
Affected
ci4-cms-erp/ci4ms
Source
security-advisories@github.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.