CVE-2026-28431

CRITICAL EPSS 16.1%
Published Mar 10, 20263mo ago · Modified Jun 17, 20262w ago
9.2 CVSS 4.0
Critical
Find Similar
Published Mar 10, 2026 3mo ago
Last Modified Jun 17, 2026 2w ago

Description

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 Details

Base Score
9.2
Exploitability
—
Impact
—
Vector string
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
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope X

Threat Intelligence

EPSS Exploit Probability
16.1% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available

Weaknesses 1

CWE-285

Affected Products 1

VendorProductVersionRange
misskeymisskey*≥8.45.0  –  <2026.3.1

References 1

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

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.