CVE-2026-2557 cskefu File Upload MediaController.java upload cross site scripting

Medium 5.1 Published 16 Feb 2026 Updated 23 Feb 2026

Remote attackers can inject malicious scripts via file upload in cskefu, potentially executing code or bypassing security controls.

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: None listed

What is CVE-2026-2557?

CVE-2026-2557 is a medium-severity cross-site scripting vulnerability in cskefu, published on 16 Feb 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

A vulnerability was detected in cskefu up to 8.0.1. Impacted is the function Upload of the file com/cskefu/cc/controller/resource/MediaController.java of the component File Upload. The manipulation results in cross site scripting. The attack may be launched remotely. The exploit is now public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

Weakness: CWE-94, CWE-79

Which versions are affected by CVE-2026-2557?

It affects 1 product.

Products include Cskefu Cskefu.

How do I fix CVE-2026-2557?

No fix has been published for CVE-2026-2557 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-2026-2557 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-2557 exists.

Sources

Also known as GHSA-ggg6-jj2q-72rr.