CVE-2026-28431: Misskey lacks proper authorization checks and input validation
Misskey is an open source, federated social media platform. All Misskey servers running versions 8.45.0 and later, but prior to 2026.3.1, contain a vulnerability that allows bad actors access to data that they ordinarily wouldn't be able to access due to insufficient permission checks and proper input validation. This vulnerability occurs regardless of whether federation is enabled or not. This vulnerability could lead to a significant data breach. This vulnerability is fixed in 2026.3.1.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-28431?
The severity of CVE-2026-28431 is classified as high due to the potential unauthorized access to sensitive data.
How do I fix CVE-2026-28431?
To fix CVE-2026-28431, upgrade Misskey to version 2026.3.1 or later.
What versions of Misskey are affected by CVE-2026-28431?
CVE-2026-28431 affects all Misskey servers running versions 8.45.0 through 2026.3.0.
What type of vulnerability is CVE-2026-28431?
CVE-2026-28431 is a security vulnerability involving improper authorization checks and insufficient input validation.
Who is impacted by CVE-2026-28431?
Users of Misskey servers running vulnerable versions may be impacted by unauthorized data access.