Insufficient Permission Checks in Misskey by Misskey Dev
CVE-2026-28431

9.2CRITICAL

Key Information:

Vendor

Misskey-dev

Status
Misskey
Vendor
CVE Published:
9 March 2026

What is CVE-2026-28431?

Misskey, an open-source federated social media platform, is affected by a vulnerability that allows unauthorized access to sensitive data due to inadequate permission checks and insufficient input validation. This issue exists across all server versions from 8.45.0 up to but not including 2026.3.1, regardless of the federation feature being used. Remediation is available in version 2026.3.1, emphasizing the importance of timely updates to safeguard user data.

Affected Version(s)

misskey >= 8.45.0, < 2026.3.1

References

https://github.com/misskey-dev/misskey/security/advisorie...
x_refsource_CONFIRM

CVSS V4

Score:
9.2
Severity:
CRITICAL
Confidentiality:
High
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.