CVE-2026-0817 CampaignEvents API missing authorization exposes meeting and chat URLs
Attackers can access private meeting and chat URLs without authorization, exposing sensitive information in MediaWiki installations using the CampaignEvents extension.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-0817?
CVE-2026-0817 is a medium-severity missing authorization vulnerability in Wikimedia Foundation MediaWiki - CampaignEvents extension, published on 9 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-862
Which versions are affected by CVE-2026-0817?
It affects 1 product.
Products include Wikimedia Campaignevents.
How do I fix CVE-2026-0817?
No fix has been published for CVE-2026-0817 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-0817 being exploited?
There is no known exploitation of CVE-2026-0817 in the wild and no public exploit code.
Sources
Also known as GHSA-5v56-6x55-vhpv.