Vulnerability · Published Dec 12, 2025 · Assigned by jpcert
CVE-2025-64781
Medium 4.7
In plain English
A medium-severity security flaw in GroupSession byCloud from Japan Total System Co.,Ltd.. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 11% of all known vulnerabilities).
Severity (CVSS 3.0)4.7Medium
Exploit odds (30 days)0.2%top 89.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
In GroupSession Free edition prior to ver5.7.1, GroupSession byCloud prior to ver5.7.1, and GroupSession ZION prior to ver5.7.1, "External page display restriction" is set to "Do not limit" in the initial configuration. With this configuration, the user may be redirected to an arbitrary website when accessing a specially crafted URL.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Japan Total System Co.,Ltd. | GroupSession Free edition | prior to ver5.7.1 |
| Japan Total System Co.,Ltd. | GroupSession byCloud | prior to ver5.7.1 |
| Japan Total System Co.,Ltd. | GroupSession ZION | prior to ver5.7.1 |
Weakness: CWE-1188 · Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N