What’s Vulnerable › Vulnerabilities
CVE-2025-66284
- Severity: medium (CVSS 4.8 v4.0)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.2% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2025-12-12 · updated 2026-10-07
- Weakness: CWE-79
Description
Stored cross-site scripting vulnerabilities exist in GroupSession Free edition prior to ver5.7.1, GroupSession byCloud prior to ver5.7.1, and GroupSession ZION prior to ver5.7.1. A logged-in user can prepare a malicious page or URL, and an arbitrary script may be executed on the web browser when another user accesses it.
Affected products
- Japan Total System Co.,Ltd. GroupSession: before 5.7.1 — fixed in 5.7.1
How to fix
Upgrade to a fixed version: Japan Total System Co.,Ltd. GroupSession 5.7.1. Check the vendor advisory for mitigations.
References
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