VDB-336097 · CVE-2025-64781 · GCVE-0-2025-64781

Japan Total System GroupSession Free Edition External Page insecure default initialization of resource

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
4.4	$0-$5k	0.00

Summaryinfo

A vulnerability classified as problematic has been found in Japan Total System GroupSession Free Edition, GroupSession byCloud and GroupSession ZION. This vulnerability affects unknown code of the component External Page. This manipulation causes insecure default initialization of resource. This vulnerability is tracked as CVE-2025-64781. The attack is possible to be carried out remotely. No exploit exists. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic was found in Japan Total System GroupSession Free Edition, GroupSession byCloud and GroupSession ZION (version now known). Affected by this vulnerability is some unknown processing of the component External Page. The manipulation with an unknown input leads to a insecure default initialization of resource vulnerability. The CWE definition for the vulnerability is CWE-1188. The product initializes or sets a resource with a default that is intended to be changed by the administrator, but the default is not secure. As an impact it is known to affect integrity. The summary by CVE is:

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.

The advisory is shared at groupsession.jp. This vulnerability is known as CVE-2025-64781 since 11/27/2025. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available.

Upgrading eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Cloud Software

Vendor

Japan Total System

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: 4.5
VulDB Meta Temp Score: 4.4

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 4.7
CNA Vector (jpcert): 🔒

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Insecure default initialization of resource
CWE: CWE-1188
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

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-2025-64781 (🔒)
GCVE (CVE): GCVE-0-2025-64781
GCVE (VulDB): GCVE-100-336097

Entryinfo

Created: 12/12/2025 07:27
Changes: 12/12/2025 07:27 (74)
Complete: 🔍
Cache ID: 216::103