Cyber Posture

CVE-2025-67478

High

Published: 03 February 2026

Published
03 February 2026
Modified
14 April 2026
KEV Added
—
Patch
—
CVSS Score 8.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS Score 0.0002 5.8th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-67478 is a high-severity an unspecified weakness vulnerability in Mediawiki Checkuser. Its CVSS base score is 8.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 5.8th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified are NIST 800-53 RA-5 (Vulnerability Monitoring and Scanning) and SI-2 (Flaw Remediation).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190) and 1 other technique. What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

SI-2 Flaw Remediation good match
prevent

Directly requires identification, reporting, and timely remediation of software flaws like CVE-2025-67478 in the CheckUser extension's UserMailer.php.

RA-5 Vulnerability Monitoring and Scanning good match
detect

Enables regular vulnerability scanning to identify the presence of CVE-2025-67478 in deployed CheckUser versions before exploitation.

SI-5 Security Alerts, Advisories, and Directives partial match
detect

Provides mechanisms to receive and distribute security alerts about vulnerabilities like CVE-2025-67478, facilitating prompt patching.

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1204.001 Malicious Link Execution
An adversary may rely upon a user clicking a malicious link in order to gain execution.
attack.mitre.org →
Why these techniques?

Network-accessible web app vuln with UI:R and full CIA impact maps to public app exploitation and malicious link user execution.

Confidence: MEDIUM · MITRE ATT&CK Enterprise v18.1

NVD 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.

Deeper analysisAI

CVE-2025-67478 is a vulnerability in the Wikimedia Foundation's CheckUser extension, specifically associated with the program file includes/Mail/UserMailer.php. It affects CheckUser versions from * before 1.39.14, 1.43.4, and 1.44.1. The vulnerability has a CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H) and is categorized under NVD-CWE-noinfo.

An unauthenticated attacker with network access can exploit this vulnerability with low attack complexity, though it requires user interaction such as clicking a malicious link or similar action. Successful exploitation enables high-impact consequences, including unauthorized access to confidential data, modification of system integrity, and disruption of availability.

Mitigation details are available in the referenced Phabricator task at https://phabricator.wikimedia.org/T385403, which likely includes patch information for the affected CheckUser versions.

Details

CWE(s)
NVD-CWE-noinfo

Affected Products

mediawiki
checkuser
1.44.0 · 1.39.0 — 1.39.14 · 1.43.0 — 1.43.4

CVEs Like This One

CVE-2025-67484Same vendor: Mediawiki
CVE-2026-0669Same vendor: Mediawiki

References