CVE-2025-6591Network attack vector

HTML injection via unescaped contribution-feed messages

Published Feb 2, 2026 · Updated Feb 2, 2026

HTML injection in MediaWiki before 1.39.13, 1.42.7, 1.43.2, and 1.44.0 allows attackers to place raw markup in contribution feeds. ApiFeedContributions inserts the Contributions and colon-separator content-language messages into feed titles and descriptions without selecting escaped output. Reachability requires control of content-language messages and a feed consumer that processes the injected markup; Wikimedia did not establish exploitability in a feed reader.

CVSS severity0.0
None
EPSS probability0.46%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

HTML injection in MediaWiki before 1.39.13, 1.42.7, 1.43.2, and 1.44.0 allows attackers to place raw markup in contribution feeds. ApiFeedContributions inserts the Contributions and colon-separator content-language messages into feed titles and descriptions without selecting escaped output. Reachability requires control of content-language messages and a feed consumer that processes the injected markup; Wikimedia did not establish exploitability in a feed reader.

The record

CVE
CVE-2025-6591
Published
Feb 2, 2026
Updated
Feb 2, 2026
Vendor
Wikimedia Foundation
Product
MediaWiki
Classifications
CWE-79
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=* <1.39.13, 1.42.7 1.43.2, 1.44.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Wikimedia Foundation · MediaWikiversion=* <1.39.13, 1.42.7 1.43.2, 1.44.0

Published CVSS scores

4.7CISA ADP VulnrichmentCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N
0.0Wikimedia FoundationCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:A/VC:N/VI:N/VA:N/SC:N/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.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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