Medium severity · published Aug 5, 2021
CVE-2021-37859
Fixed a bypass for a reflected cross-site scripting vulnerability affecting OAuth-enabled instances of Mattermost
6.1
CVSS
3.3%
EPSS
No
On KEV
Description
Fixed a bypass for a reflected cross-site scripting vulnerability affecting OAuth-enabled instances of Mattermost.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)3.3% · higher than 88% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MA
Mattermost · Mattermost
5.32.0 before 5.34.5; 5.35.0 before 5.35.4; 5.36.0 before 5.36.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-37859
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-37859
Vendor Advisory
https://mattermost.com/security-updates/
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