Medium severity · published Dec 17, 2021
CVE-2021-37863
Mattermost 6.0 and earlier fails to sufficiently validate parameters during post creation, which allows authenticated attackers to cause a client-side crash of the web application…
5.7
CVSS
0.9%
EPSS
No
On KEV
Description
Mattermost 6.0 and earlier fails to sufficiently validate parameters during post creation, which allows authenticated attackers to cause a client-side crash of the web application via a maliciously crafted post.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.9% · higher than 58% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MS
Mattermost Server · Mattermost
through 6.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-37863
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-37863
Permissions Required
https://hackerone.com/reports/1253732
Vendor Advisory
https://mattermost.com/security-updates/
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