High severity · published Jun 19, 2020
CVE-2019-20888
An issue was discovered in Mattermost Server before 5.7, 5.6.3, 5.5.2, and 4.10.5
7.5
CVSS
1.1%
EPSS
No
On KEV
Description
An issue was discovered in Mattermost Server before 5.7, 5.6.3, 5.5.2, and 4.10.5. It allows attackers to cause a denial of service (memory consumption) via an outgoing webhook or a slash command integration.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.1% · higher than 66% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MS
Mattermost Server · Mattermost
before 4.10.5; 5.5.0 before 5.5.2; 5.6.0 before 5.6.3; 5.7.0; 5.7.0; 5.7.0; +3 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2019-20888
CVE.org
https://www.cve.org/CVERecord?id=CVE-2019-20888
Vendor Advisory
https://mattermost.com/security-updates/
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