Description
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.
Published: 2026-05-11
Score: 4.8 Medium
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

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Remediation

No vendor fix or workaround currently provided.

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Tracking

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Advisories

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References
History

Thu, 14 May 2026 16:45:00 +0000

Type Values Removed Values Added
First Time appeared Mediawiki
Mediawiki checkuser
CPEs cpe:2.3:a:mediawiki:checkuser:*:*:*:*:*:mediawiki:*:*
Vendors & Products Mediawiki
Mediawiki checkuser
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N'}


Mon, 11 May 2026 17:30:00 +0000

Type Values Removed Values Added
First Time appeared Wikimedia
Wikimedia checkuser
Vendors & Products Wikimedia
Wikimedia checkuser

Mon, 11 May 2026 16:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Mon, 11 May 2026 15:30:00 +0000

Type Values Removed Values Added
Description 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.
Title Suggested investigations: Handle suppressed usernames
Weaknesses CWE-200
References
Metrics cvssV4_0

{'score': 4.8, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/R:U'}


Subscriptions

Mediawiki Checkuser
Wikimedia Checkuser
cve-icon MITRE

Status: PUBLISHED

Assigner: wikimedia-foundation

Published:

Updated: 2026-05-11T15:51:32.487Z

Reserved: 2026-03-25T17:15:46.521Z

Link: CVE-2026-34090

cve-icon Vulnrichment

Updated: 2026-05-11T15:51:27.108Z

cve-icon NVD

Status : Analyzed

Published: 2026-05-11T16:17:30.407

Modified: 2026-05-14T16:42:57.203

Link: CVE-2026-34090

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-05-11T17:15:39Z

Weaknesses