Cross-site scripting in Japan Total System Co.,Ltd. GroupSession
Priority LOW 23CWE-79Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- High
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- Cross-site scripting
- Confidentiality · integrity · availability
- Low · Low · None
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-79.
Summary
Cross-site scripting vulnerability in GroupSession (GroupSession Free edition from ver2.2.0 to the version prior to ver5.1.0, GroupSession byCloud from ver3.0.3 to the version prior to ver5.1.0, and GroupSession ZION from ver3.0.3 to the version prior to ver5.1.0) allows a remote attacker to inject an arbitrary script by sending a specially crafted request to a specific URL.
Why it matters now
EPSS 0.0064 50th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Japan Total System Co.,Ltd. | GroupSession | GroupSession Free edition from ver2.2.0 to the version prior to ver5.1.0, GroupSession byCloud from ver3.0.3 to the version prior to ver5.1.0, and GroupSession ZION from ver3.0.3 to the version prior to ver5.1.0 | — | No fix listed | CNA |
- GroupSession VendorJapan Total System Co.,Ltd. Affected GroupSession Free edition from ver2.2.0 to the version prior to ver5.1.0, GroupSession byCloud from ver3.0.3 to the version prior to ver5.1.0, and GroupSession ZION from ver3.0.3 to the version prior to ver5.1.0 Fixed in — No fix listed CNA
CPE configurations NVD · 3
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:groupsession:groupsession:*:*:*:*:free:*:*:* | 2.20 to before 5.1.0 | Vulnerable | Japan Total System Co.,Ltd. |
| cpe:2.3:a:groupsession:groupsession_bycloud:*:*:*:*:*:*:*:* | 3.0.3 to before 5.1.0 | Vulnerable | Japan Total System Co.,Ltd. |
| cpe:2.3:a:groupsession:groupsession_zion:*:*:*:*:*:*:*:* | 3.0.3 to before 5.1.0 | Vulnerable | Japan Total System Co.,Ltd. |
- cpe:2.3:a:groupsession:groupsession:*:*:*:*:free:*:*:* Versions 2.20 to before 5.1.0 Vulnerable ·Japan Total System Co.,Ltd.
- cpe:2.3:a:groupsession:groupsession_bycloud:*:*:*:*:*:*:*:* Versions 3.0.3 to before 5.1.0 Vulnerable ·Japan Total System Co.,Ltd.
- cpe:2.3:a:groupsession:groupsession_zion:*:*:*:*:*:*:*:* Versions 3.0.3 to before 5.1.0 Vulnerable ·Japan Total System Co.,Ltd.
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2021-20787
- 2026-10-03 Alias added: GHSA-536v-gg7v-fc83
- 2026-10-23 EPSS moved to the 50th–90th percentile
References
More Japan Total System Co.,Ltd. Groupsession vulnerabilities
- TI-2021-04088 Incorrect permission assignment in Japan Total System Co.,Ltd. GroupSession Free edition… CVSS 3.1HIGH 7.5
- TI-2025-38316 GroupSession Free edition prior to ver5.3.0, GroupSession byCloud prior to ver5.3.3, and… CVSS 4.0MEDIUM 6.9
- TI-2021-04090 Path traversal in Japan Total System Co.,Ltd. GroupSession Free edition, GroupSession… CVSS 3.1MEDIUM 6.8
- TI-2017-01466 Information disclosure in Japan Total System Co.,Ltd. GroupSession CVSS 3.0MEDIUM 6.5
- TI-2025-38294 Authorization bypass in Japan Total System Co.,Ltd. GroupSession Free edition CVSS 4.0MEDIUM 5.3
- TI-2021-04089 Open redirect in Japan Total System Co.,Ltd. GroupSession Free edition, GroupSession… CVSS 3.1MEDIUM 6.1
Sources
- CVE-2021-20787 · CVE Program
- CVE-2021-20787 · NVD
- FIRST EPSS
- GHSA-536v-gg7v-fc83 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences