CVE-2025-65120 Cross-site scripting in GroupSession Free edition

Medium 5.1 Published 12 Dec 2025 Updated 12 Dec 2025

Reflected XSS in GroupSession allows attackers to execute arbitrary scripts in user browsers via crafted URLs, requiring an upgrade to mitigate.

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-2025-65120?

CVE-2025-65120 is a medium-severity cross-site scripting vulnerability in Japan Total System Co.,Ltd. GroupSession Free edition, published on 12 Dec 2025. 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

Reflected cross-site scripting vulnerability exists in GroupSession Free edition prior to ver5.7.1, GroupSession byCloud prior to ver5.7.1, and GroupSession ZION prior to ver5.7.1. If a user accesses a crafted page or URL, an arbitrary script may be executed on the web browser of the user.

Weakness: CWE-79

Which versions are affected by CVE-2025-65120?

It affects 1 product.

Products include Groupsession Groupsession.

How do I fix CVE-2025-65120?

No fix has been published for CVE-2025-65120 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-2025-65120 being exploited?

There is no known exploitation of CVE-2025-65120 in the wild and no public exploit code.

Sources

Also known as GHSA-4w3r-95jc-3289.