CVE-2026-28431

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/misskey-dev/misskey/security/advisories/GHSA-r33c-qg3g-v9cr	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:misskey:misskey:*:*:*:*:*:*:*:*

History

13 Mar 2026, 17:18

Type	Values Removed	Values Added
CPE		cpe:2.3:a:misskey:misskey::::::::
Summary		(es) Misskey es una plataforma de redes sociales de código abierto y federada. Todos los servidores Misskey que ejecutan versiones 8.45.0 y posteriores, pero anteriores a la 2026.3.1, contienen una vulnerabilidad que permite a actores maliciosos acceder a datos a los que normalmente no podrían acceder debido a comprobaciones de permisos insuficientes y a una validación de entrada adecuada. Esta vulnerabilidad ocurre independientemente de si la federación está habilitada o no. Esta vulnerabilidad podría conducir a una violación de datos significativa. Esta vulnerabilidad está corregida en la 2026.3.1.
First Time		Misskey misskey Misskey
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5
References	~~() https://github.com/misskey-dev/misskey/security/advisories/GHSA-r33c-qg3g-v9cr -~~	() https://github.com/misskey-dev/misskey/security/advisories/GHSA-r33c-qg3g-v9cr - Vendor Advisory

10 Mar 2026, 07:43

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-10 07:43

Updated : 2026-03-13 17:18

NVD link : CVE-2026-28431

Mitre link : CVE-2026-28431

CVE.ORG link : CVE-2026-28431

JSON object : View

Products Affected

misskey

misskey

CWE

CWE-285

Improper Authorization

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