High severity · published Aug 25, 2023
CVE-2023-4478
Mattermost fails to restrict which parameters' values it takes from the request during signup allowing an attacker to register users as inactive, thus blocking them from later…
8.2
CVSS
0.5%
EPSS
No
On KEV
Description
Mattermost fails to restrict which parameters' values it takes from the request during signup allowing an attacker to register users as inactive, thus blocking them from later accessing Mattermost without the system admin activating their accounts.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 43% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MS
Mattermost Server · Mattermost
before 7.8.9; 7.9.0 before 7.10.5; 8.0.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-4478
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-4478
Vendor Advisory
https://mattermost.com/security-updates
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