CVE-2026-34560 CI4MS: Logs Full Account Takeover for All-Roles & Privilege-Escalation via Stored DOM XSS

Critical 9.1 Published 1 Apr 2026 Updated 2 Apr 2026

Stored DOM XSS in CI4MS logs allows attackers to execute scripts when admins view logs, leading to 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-2026-34560?

CVE-2026-34560 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 renders user-controlled input unsafely within the logs interface. If any stored XSS payload exists within logged data, it is rendered without proper output encoding. This issue becomes a Blind XSS scenario because the attacker does not see immediate execution. Instead, the payload is stored within application logs and only executes later when an administrator views the logs page. This issue has been patched in version 0.31.0.0.

Weakness: CWE-79

Which versions are affected by CVE-2026-34560?

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-2026-34560?

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-2026-34560 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-34560 exists.

Sources

Also known as GHSA-r4v5-rwr2-q7r4.