CVE-2026-34563 CI4MS: Backup Management Full Account Takeover for All-Roles & Privilege-Escalation via Stored DOM Blind XSS

Critical 9.1 Published 1 Apr 2026 Updated 2 Apr 2026

Attackers can achieve full account takeover and privilege escalation via stored blind XSS in the backup management module of CI4MS.

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-2026-34563?

CVE-2026-34563 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 handling backup uploads and processing backup metadata. An attacker can inject a malicious JavaScript payload into the backup filename via the uploaded xss.sql, which uses SQL functionality to insert the XSS payload server-side. This stored payload is later rendered unsafely in multiple backup management views without proper output encoding, leading to stored blind cross-site scripting (Blind XSS). This issue has been patched in version 0.31.0.0.

Weakness: CWE-79

Which versions are affected by CVE-2026-34563?

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-2026-34563?

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-2026-34563 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-34563 exists.

Sources

Also known as GHSA-85m8-g393-jcxf.