CVE-2021-20789 json
Open redirect vulnerability in GroupSession (GroupSession Free edition from ver2.2.0 to the version prior to ver5.1.0, GroupSession byCloud…
published 5y ago modified 4mo ago also EUVD-2021-8201
- cvss
- 6.1
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.9%
- EPSS 0.9% chance of exploitation in 30 days, percentile 59%
- public exploits
- 0
- none known
Summary
Open redirect 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 redirect a user to an arbitrary web site and conduct a phishing attack via a specially crafted URL.
Patch / fix
- groupsession groupsession 5.1.0
- groupsession groupsession_bycloud 5.1.0
- groupsession groupsession_zion 5.1.0
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Check with FencerExploit prediction
0.87% chance of exploitation in the next 30 days, higher than 59% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| NVD | 2.0 | 5.8 | AV:N/AC:M/Au:N/C:P/I:P/A:N |
Affected products
- Japan Total System Co.,Ltd. GroupSession
Classification
- Weakness
-
- CWE-601 URL Redirection to Untrusted Site
References
-
groupsession.jp
/info/info-news/security202107
vendor-advisory
-
jvn.jp
/en/jp/JVN86026700/index.html
third-party-advisory
Sources
- CVE List CVE-2021-20789
- NVD CVE-2021-20789
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