Medium severity · published Jun 19, 2020
CVE-2019-20844
An issue was discovered in Mattermost Server before 5.18.0, 5.17.2, 5.16.4, 5.15.4, and 5.9.7
6.5
CVSS
0.4%
EPSS
No
On KEV
Description
An issue was discovered in Mattermost Server before 5.18.0, 5.17.2, 5.16.4, 5.15.4, and 5.9.7. An attacker can spoof a direct-message channel by changing the type of a channel.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 37% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MS
Mattermost Server · Mattermost
before 5.9.7; 5.15.0 before 5.15.4; 5.16.0 before 5.16.4; 5.17.0 before 5.17.2; 5.18.0; 5.18.0; +2 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2019-20844
CVE.org
https://www.cve.org/CVERecord?id=CVE-2019-20844
Vendor Advisory
https://mattermost.com/security-updates/
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