CVE-2026-45138 CI4MS: Stored XSS in Blog Content via Broken `html_purify` Validation Rule
Stored XSS in CI4MS blog content allows attackers to execute scripts in visitors' browsers, including admins, due to broken sanitization.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-45138?
CVE-2026-45138 is a medium-severity cross-site scripting vulnerability in ci4-cms-erp ci4ms, published on 19 Jul 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
CI4MS is a CodeIgniter 4-based content management system skeleton. Prior to version 0.31.9.0, the custom `html_purify` validation rule used to sanitize blog post bodies relies on by-reference mutation (`?string &$str`), but CodeIgniter 4's validator passes a local copy of the value, so the sanitized text is silently discarded. The Blog controller writes `$lanData['content']` directly into `blog_langs.content`, and the public template echoes it without escaping — yielding stored XSS executable in any visitor's browser, including the superadmin when previewing or editing posts. Version 0.31.9.0 patches the issue.
Weakness: CWE-79
Which versions are affected by CVE-2026-45138?
2 open source packages ship an affected version, including ci4-cms-erp/ci4ms.
| Package | Affected | Fixed in |
|---|---|---|
ci4-cms-erp/ci4ms Packagist | All versions | 0.31.9.0 |
ci4-cms-erp/ci4ms Packagist | All versions | 0.31.9.0 |
How do I fix CVE-2026-45138?
Upgrade ci4-cms-erp/ci4ms to 0.31.9.0 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-2026-45138 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-45138 exists.
Sources
Also known as GHSA-2m69-jmvh-6chr.