High severity · published Jun 19, 2020
CVE-2018-21263
An issue was discovered in Mattermost Server before 4.7.0, 4.6.2, and 4.5.2
8.8
CVSS
0.9%
EPSS
No
On KEV
Description
An issue was discovered in Mattermost Server before 4.7.0, 4.6.2, and 4.5.2. An attacker could authenticate to a different user's account via a crafted SAML response.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.9% · higher than 60% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MS
Mattermost Server · Mattermost
before 4.5.2; 4.6.0 before 4.6.2; 4.7.0; 4.7.0; 4.7.0; 4.7.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2018-21263
CVE.org
https://www.cve.org/CVERecord?id=CVE-2018-21263
Vendor Advisory
https://mattermost.com/security-updates/
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