CRITICAL🇵🇱 Wersja polska

CVE-2026-28431

CVSS 9.2v4.0pub. 2026-03-10upd. 2026-03-13

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.

🤖 AI Analysis
How it works

The vulnerability classified as CWE-285 (Improper Authorization) consists of the fact that the Misskey server does not perform sufficient permission checks when processing requests. An attacker can send appropriately crafted network requests that bypass authorization mechanisms and enable access to protected resources. The vulnerability occurs regardless of whether federation with other instances is enabled on the server.

Impact

An attacker without any permissions can gain access to user data and other protected server resources that they should not normally have access to. This can result in a serious data breach affecting data confidentiality.

Mitigation & patch

Misskey should be updated to version 2026.3.1, where the vulnerability has been fixed. The patch is available in the project repository on GitHub according to security advisory GHSA-r33c-qg3g-v9cr.

Who is affected

All Misskey servers running versions from 8.45.0 (inclusive) to versions earlier than 2026.3.1

Analysis generated by Claude AI (Anthropic) based on NVD data. Always verify with vendor.
CVSS Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

  • Misskey

    APP
    Misskey
    8.45.0 – 2026.3.1 (excl.)
🔵
CHECK WITH VENDOR
No clear patch data available. Check vendor references.
CWE
References

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