CVE-2026-34564 CI4MS: Menu Management (Pages) Full Account Takeover for All-Roles & Privilege-Escalation via Stored DOM XSS

Critical 9.1 Published 1 Apr 2026 Updated 2 Apr 2026

Attackers can execute stored DOM XSS in CI4MS menu management to achieve full account takeover and privilege escalation.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2026-34564?

CVE-2026-34564 is a critical cross-site scripting vulnerability in ci4-cms-erp ci4ms, published on 1 Apr 2026. Any signed-in user can exploit it over the network, with no action from the victim.

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 version 0.31.0.0, the application fails to properly sanitize user-controlled input when adding Pages to navigation menus through the Menu Management functionality. Page-related data selected via the Pages section is stored server-side and rendered without proper output encoding. This stored payload is later rendered unsafely within administrative interfaces and public-facing navigation menus, leading to stored DOM-based cross-site scripting (XSS). This issue has been patched in version 0.31.0.0.

Weakness: CWE-79

Which versions are affected by CVE-2026-34564?

2 open source packages ship an affected version, including ci4-cms-erp/ci4ms. It affects 1 product.

Package	Affected	Fixed in
`ci4-cms-erp/ci4ms` Packagist	All versions	`0.31.0.0`
`ci4-cms-erp/ci4ms` Packagist	All versions	`0.31.0.0`

Products include Ci4-Cms-Erp Ci4ms.

How do I fix CVE-2026-34564?

Upgrade ci4-cms-erp/ci4ms to 0.31.0.0 or later.

Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.

Is CVE-2026-34564 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-34564 exists.

Sources

Also known as GHSA-g4pp-fhgf-8653.