Japan Total System GroupSession Free Edition cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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4.4$0-$5k0.00

Summaryinfo

A vulnerability marked as problematic has been reported in Japan Total System GroupSession Free Edition, GroupSession byCloud and GroupSession ZION. This issue affects some unknown processing. This manipulation causes cross site scripting. The identification of this vulnerability is CVE-2025-66284. It is possible to initiate the attack remotely. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Japan Total System GroupSession Free Edition, GroupSession byCloud and GroupSession ZION (the affected version is unknown) and classified as problematic. Affected by this vulnerability is an unknown code. The manipulation with an unknown input leads to a cross site scripting vulnerability. The CWE definition for the vulnerability is CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. As an impact it is known to affect integrity. The summary by CVE is:

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.

The advisory is shared at groupsession.jp. This vulnerability is known as CVE-2025-66284 since 11/27/2025. The exploitation appears to be easy. The attack can be launched remotely. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1059.007 for this issue.

Upgrading eliminates this vulnerability.

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Productinfo

Type

Vendor

Name

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 4.4
VulDB Meta Temp Score: 4.4

VulDB Base Score: 3.5
VulDB Temp Score: 3.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.4
CNA Vector (jpcert): 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Cross site scripting
CWE: CWE-79 / CWE-94 / CWE-74
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Timelineinfo

11/27/2025 CVE reserved
12/12/2025 +15 days Advisory disclosed
12/12/2025 +0 days VulDB entry created
12/12/2025 +0 days VulDB entry last update

Sourcesinfo

Advisory: groupsession.jp
Status: Confirmed

CVE: CVE-2025-66284 (🔒)
GCVE (CVE): GCVE-0-2025-66284
GCVE (VulDB): GCVE-100-336109

Entryinfo

Created: 12/12/2025 07:29
Changes: 12/12/2025 07:29 (74)
Complete: 🔍
Cache ID: 216::103

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