CVE-2026-86244 FastAdmin User Controller User.php login cross site scripting
Remote attackers can execute arbitrary scripts via the login URL parameter in FastAdmin, potentially leading to session hijacking or code execution.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-86244?
CVE-2026-86244 is a medium-severity cross-site scripting vulnerability in FastAdmin, published on 7 Sep 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
A security vulnerability has been detected in FastAdmin up to 1.2.0.20210401_beta. Affected is the function register/login of the file application/index/controller/User.php of the component User Controller. Such manipulation of the argument url leads to cross site scripting. The attack may be performed from remote. The exploit has been disclosed publicly and may be used. Upgrading to version 1.2.1.20210731_beta is able to address this issue. The name of the patch is b3d32e2bf3637488cfe2fc58a27a9d2475b2b51b. It is recommended to upgrade the affected component.
Which versions are affected by CVE-2026-86244?
How do I fix CVE-2026-86244?
No fix has been published for CVE-2026-86244 yet. Limit exposure of the affected software until one is available.
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-2026-86244 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-86244 exists.
Sources
Also known as GHSA-h6hc-9p4p-wf6h.