CVE-2021-20786 json
Cross-site request forgery (CSRF) vulnerability in GroupSession (GroupSession Free edition from ver2.2.0 to the version prior to ver5.1.0,…
published 2021-07-28 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-8198
- cvss
- 4.3
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 39%
- public exploits
- 0
- none known
Summary
Cross-site request forgery (CSRF) 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 hijack the authentication of administrators via a specially crafted URL.
Patch / fix
- groupsession groupsession 5.1.0
- groupsession groupsession_bycloud 5.1.0
- groupsession groupsession_zion 5.1.0
Exploit prediction
0.45% chance of exploitation in the next 30 days, higher than 39% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 4.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N |
| NVD | 2.0 | 4.3 | AV:N/AC:M/Au:N/C:N/I:P/A:N |
Affected products
- Japan Total System Co.,Ltd. GroupSession
Classification
- Weakness
-
- CWE-352 Cross-Site Request Forgery
References
-
groupsession.jp
/info/info-news/security202107
vendor-advisory
-
jvn.jp
/en/jp/JVN86026700/index.html
third-party-advisory
Sources
- CVE List CVE-2021-20786
- NVD CVE-2021-20786
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