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.
Affected products
groupsession: groupsession
References2
- groupsession.jp/info/info-news/security20251208 Vendor Advisory
- jvn.jp/en/jp/JVN19940619/ Third Party Advisory
Metrics
- CVSS 4.0
-
5.3
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 9 · as of 11 November 2026
- CWE
- CWE-639
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