Critical severity · published Jun 19, 2020
CVE-2017-18883
An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2, when serving as an OAuth 2.0 Service Provider
9.1
CVSS
1.1%
EPSS
No
On KEV
Description
An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2, when serving as an OAuth 2.0 Service Provider. There is low entropy for authorization data.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
None
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 4.1.2; 4.2.0 before 4.2.1; 4.3.0; 4.3.0; 4.3.0; 4.3.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2017-18883
CVE.org
https://www.cve.org/CVERecord?id=CVE-2017-18883
Vendor Advisory
https://mattermost.com/security-updates/
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