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MediawikiCMS

CVE-2026-58026

MEDIUM · 5.7 CVSS v3.1 Published 2026-07-01
Fix available
A fix is available. Upgrade to 1.43.9 / 1.44.6 or later.
See remediation →
61/100
Remediation priority · Elevated
Remotely reachable 7 weeks old

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Exposure of Sensitive Information to an Unauthorized Actor vulnerability in Wikimedia Foundation MediaWiki. This vulnerability is associated with program files includes/Parser/Parser.Php. This issue affects MediaWiki: from * before 1.46.0, 1.45.4, 1.44.6, 1.43.9.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

An information disclosure vulnerability exists in MediaWiki's Parser component (includes/Parser/Parser.php) that allows unauthorized access to sensitive information. The vulnerability affects multiple unsupported MediaWiki branches prior to versions 1.46.0, 1.45.4, 1.44.6, and 1.43.9.

MitigationUpgrade MediaWiki to a supported patched version (1.46.0 or later, or 1.45.4+/1.44.6+/1.43.9+ depending on the branch in use). Review parser output and cache to ensure no sensitive data was exposed prior to patching.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
MediawikiCMS
Affected:>= 1.43.0, < 1.43.9>= 1.44.0, < 1.44.6>= 1.45.0, < 1.45.4= 1.46.0

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check installed MediaWiki version
    Locate the MediaWiki installation directory and check the version file. Typically found in includes/Parser/Parser.php or by accessing /api.php?action=query&meta=siteinfo&format=json. Alternatively, check the file 'includes/Defines.php' for the $wgVersion variable, or look at the 'LocalSettings.php' file which may contain version information.
    Affected if The installed version is 1.43.0 through 1.43.8, 1.44.0 through 1.44.5, 1.45.0 through 1.45.3, or exactly 1.46.0
  2. Verify Parser component is in use
    Confirm that the MediaWiki Parser component (includes/Parser/Parser.php) exists and is being utilized. This can be verified by checking if the Parser.php file exists in the installation and by examining if pages are being rendered through the parser (e.g., check if the wiki is actively parsing wikitext content).
    Affected if The Parser component exists and is actively parsing content, which is the default behavior for any running MediaWiki installation
  3. Inspect Parser output for sensitive data exposure
    Review recent pages or content that was rendered by the Parser. Check the 'page_content' table in the database for any stored output, or examine the parser cache if enabled (typically in the 'objectcache' table). Look for any unexpected sensitive data in parsed content that should not be visible.
    Affected if Sensitive information that was not intentionally included in the wikitext appears in the rendered page output or parser cache

A user is affected if their MediaWiki installation version falls within the vulnerable ranges (1.43.0-1.43.8, 1.44.0-1.44.5, 1.45.0-1.45.3, or exactly 1.46.0) and the Parser component is in use, which is the default configuration.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 1.43.9 / 1.44.6 / 1.45.4 or later
Fixed in 1.43.91.44.61.45.4
Interim mitigation

Upgrade MediaWiki to a supported patched version (1.46.0 or later, or 1.45.4+/1.44.6+/1.43.9+ depending on the branch in use). Review parser output and cache to ensure no sensitive data was exposed prior to patching.

Recommended fix High confidence

1.46.1 (or 1.45.4/1.44.6/1.43.9 depending on your branch)

  1. Determine your current MediaWiki version by checking the includes/DefaultSettings.php file or the Special:Version page
  2. Identify which version branch you are running (1.43.x, 1.44.x, 1.45.x, or 1.46.x)
  3. Download MediaWiki version 1.46.1 (or 1.45.4, 1.44.6, or 1.43.9 depending on your branch) from https://www.mediawiki.org/wiki/Download
  4. Backup your database and all configuration files before upgrading
  5. Follow the standard MediaWiki upgrade process: upload the new files, run the update.php maintenance script (php maintenance/update.php), and clear any caches
  6. Verify the upgrade was successful by checking Special:Version shows the new version

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Mediawiki Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing6.0 h
  • Review / QA3.0 h
15.0 hours of engineering $2,560
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Scan for this in your stack

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-58026 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data