Low severity · published Sep 14, 2026
CVE-2023-37252
An issue was discovered in the CheckUser extension for MediaWiki through 1.39.3
3.1
CVSS
0.2%
EPSS
No
On KEV
Description
An issue was discovered in the CheckUser extension for MediaWiki through 1.39.3. Special:CheckUserLog shows usernames that have been hidden.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
Attack vector
Network
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 15% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CH
CheckUser · MediaWiki
before 1.35.11; 1.36.0 before 1.38.7; 1.39.0 before 1.39.4 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-37252
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-37252
phabricator.wikimedia.org
https://phabricator.wikimedia.org/T330968
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