Medium severity · published Jun 19, 2020
CVE-2018-21257
An issue was discovered in Mattermost Server before 5.1
5.3
CVSS
0.8%
EPSS
No
On KEV
Description
An issue was discovered in Mattermost Server before 5.1. It allows attackers to bypass intended access restrictions (for setting a channel header) via the Channel header slash command API.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.8% · higher than 57% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MS
Mattermost Server · Mattermost
before 5.1.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2018-21257
CVE.org
https://www.cve.org/CVERecord?id=CVE-2018-21257
Vendor Advisory
https://mattermost.com/security-updates/
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