High severity · published Feb 3, 2026
CVE-2025-67478
Wrong E-Mail address composition for usernames with a comma and Umlauts in it like "Döe, Jähn"
8.8
CVSS
0.4%
EPSS
No
On KEV
Description
Vulnerability in Wikimedia Foundation CheckUser. This vulnerability is associated with program files includes/Mail/UserMailer.Php.
This issue affects CheckUser: from * before 1.39.14, 1.43.4, 1.44.1.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 29% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CH
CheckUser · Wikimedia Foundation
before 1.39.14, 1.43.4, 1.44.1 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-67478
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-67478
Broken Link
https://phabricator.wikimedia.org/T385403
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