CVE-2025-6589Network attack vector

Suppressed username disclosure via BlockList action URLs

Published Feb 2, 2026 · Updated Feb 2, 2026

Information disclosure in MediaWiki 1.42.0 and later allows remote authenticated users to view suppressed usernames in Special:BlockList. With MultiBlocks enabled, BlockListPager renders action URLs for a visible block row even when another block suppresses the same account, placing the account name in each URL. The account needs the block right but not hideuser, and disclosure is limited to the hidden username embedded in those action links.

CVSS severity2.1
Low
EPSS probability0.45%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in MediaWiki 1.42.0 and later allows remote authenticated users to view suppressed usernames in Special:BlockList. With MultiBlocks enabled, BlockListPager renders action URLs for a visible block row even when another block suppresses the same account, placing the account name in each URL. The account needs the block right but not hideuser, and disclosure is limited to the hidden username embedded in those action links.

The record

CVE
CVE-2025-6589
Published
Feb 2, 2026
Updated
Feb 2, 2026
Vendor
Wikimedia Foundation
Product
MediaWiki
Classifications
CWE-22, T1087
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Feb 2, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 2, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 1.42.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Wikimedia Foundation · MediaWikiversion=>= 1.42.0

Published CVSS scores

2.1Wikimedia FoundationCVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
T1087Account Discovery

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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