CVE-2025-61950

Unknown Unknown - Not Provided

Improper Authorization Allows Memo Modification in GroupSession

Publication date: 2025-12-12

Last updated on: 2026-02-17

Assigner: JPCERT/CC

Description

In GroupSession, a Circular notice can be created with its memo field non-editable, but the authorization check is improperly implemented. With some crafted request, a logged-in user may alter the memo field. The affected products and versions are GroupSession Free edition prior to ver5.3.0, GroupSession byCloud prior to ver5.3.3, and GroupSession ZION prior to ver5.3.2.

CVSS Scores

EPSS Scores

Probability:
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Meta Information

Published

2025-12-12

Last Modified

2026-02-17

Generated

2026-07-06

AI Q&A

2025-12-12

EPSS Evaluated

2026-07-05

NVD

CVE-2025-61950

EUVD

EUVD-2025-203022

Affected Vendors & Products

Vendor	Product	Version / Range
groupsession	groupsession	to 5.3.3 (exc)
groupsession	groupsession	to 5.3.0 (exc)
groupsession	groupsession	to 5.3.2 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-639	The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.

Attack-Flow Graph

Executive Summary

This vulnerability in GroupSession allows a logged-in user to alter the memo field of a Circular notice, which is supposed to be non-editable. The authorization check for editing the memo field is improperly implemented, enabling modification through a crafted request. It affects GroupSession Free edition prior to version 5.3.0, GroupSession byCloud prior to version 5.3.3, and GroupSession ZION prior to version 5.3.2.

Impact Analysis

The vulnerability can impact you by allowing unauthorized modification of the memo field in Circular notices within GroupSession. This could lead to integrity issues, where information in the memo field is altered without proper authorization, potentially causing misinformation or misuse of the system's notice functionality.

Mitigation Strategies

To mitigate this vulnerability, update GroupSession to the latest versions: GroupSession Free edition to version 5.3.0 or later, GroupSession byCloud to version 5.3.3 or later, and GroupSession ZION to version 5.3.2 or later. [2]

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