5.4CVSSMEDIUM
Description
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.
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:LAttack ComplexityLow
PR:LPrivileges RequiredLow
UI:RUser InteractionRequired
Scope
S:CScopeChanged
Impact
C:LConfidentialityLow
I:LIntegrityLow
A:NAvailabilityNone
Weaknesses
Affected Products
japan total system co.,ltd.commercialJPEnterprise Softwareaka groupsession bycloud, groupsession free edition, groupsession zion
Attack Graph
Products CVE Techniques Tactics
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Exploitability
Official Patch Available
MITRE ATT&CK
2 techniques Execution
Initial Access
References
Timeline
Published
Dec 12, 2025
Last Updated
Feb 17, 2026
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