CampaigneventsApplication · Wikimedia

CVE-2026-0817

MEDIUM · 5.3 CVSS v3.1 Published 2026-01-09
Patch available
A vendor patch is available. No clean upgrade release — apply the published patch.
See remediation →
62/100
Remediation priority · Elevated
Remotely reachable No privileges Zero-click Patch available

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
Missing Authorization vulnerability in Wikimedia Foundation MediaWiki - CampaignEvents extension allows Privilege Abuse.This issue affects MediaWiki - CampaignEvents extension: 1.45, 1.44, 1.43, 1.39.

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
How this class of weakness works · CWE-862

The application checks who you are but not whether you're allowed to perform a given action, so any authenticated user can reach things meant for others. This is the classic “change the ID in the URL” bug. The fix is an authorization check on every request, evaluated against the acting user's permissions.

General guidance for the missing authorization class — the official description and references above are authoritative for this specific CVE. Want a bespoke review and a reviewed fix? Ask our team →

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
CampaigneventsApplication
Affected:= 1.39= 1.43= 1.44= 1.45

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
None
User interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
None

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

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
Patch available Apply the vendor patch
Recommended fix Moderate confidence
  1. Review the vendor patch at https://gerrit.wikimedia.org/r/q/I7ed0049691258c8bd2555e599b9b88490fbe3358 to understand the authorization fix applied
  2. Apply the patch to the CampaignEvents extension in your MediaWiki installation
  3. Verify that the patch applies cleanly to your version (1.39, 1.43, 1.44, or 1.45)
  4. Test the fix by confirming that unauthorized users can no longer access privileged CampaignEvents functionality
  5. Consider upgrading to a later version of the CampaignEvents extension when available to ensure all security fixes are included

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

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Scan for this in your stack

Free · runs locally
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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-2026-0817 in production — separate from our analysis above.

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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