CVE-2026-34090

Exposure of Sensitive Information to an Unauthorized Actor vulnerability in Wikimedia Foundation CheckUser. This issue affects CheckUser: from 1.45.0 before 1.45.2.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://phabricator.wikimedia.org/T411366	Issue Tracking Patch

Configurations

Configuration 1 (hide)

cpe:2.3:a:mediawiki:checkuser:*:*:*:*:*:mediawiki:*:*

History

14 May 2026, 16:42

Type	Values Removed	Values Added
References	~~() https://phabricator.wikimedia.org/T411366 -~~	() https://phabricator.wikimedia.org/T411366 - Issue Tracking, Patch
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5
First Time		Mediawiki Mediawiki checkuser
CPE		cpe:2.3:a:mediawiki:checkuser::::::mediawiki::*

11 May 2026, 16:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-11 16:17

Updated : 2026-05-14 16:42

NVD link : CVE-2026-34090

Mitre link : CVE-2026-34090

CVE.ORG link : CVE-2026-34090

JSON object : View

Products Affected

mediawiki

checkuser

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

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