Is CVE-2025-66402 actively exploited?

CVE-2025-66402 has no public evidence of in-the-wild exploitation as of 2026-01-06.

What is the CVSS score for CVE-2025-66402?

CVE-2025-66402 has a CVSS score of 7.1 (HIGH severity). Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/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.

How do I patch CVE-2025-66402?

Patch guidance is available from misskey security advisories. CVEDatabase generates AI-assisted remediation guidance on demand for CVE-2025-66402.

Fix CVE-2025-66402 - HIGH misskey misskey

Q: Which products are affected by CVE-2025-66402?

37 products: misskey misskey, misskey misskey, misskey misskey, misskey misskey, misskey misskey, and 32 more.

Description

Misskey is an open source, federated social media platform. Starting in version 13.0.0-beta.16 and prior to version 2025.12.0, an actor who does not have permission to view favorites or clips can can export the posts and view the contents. Version 2025.12.0 fixes the issue.

CVSS Metrics

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/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
Complexity: low
Privileges: low
User Action: none
Confidentiality: undefined
Integrity: undefined
Availability: undefined
Weaknesses: CWE-862 · Missing Authorization

Metadata

Primary Vendor: MISSKEY
Published: 12/16/2025
Last Modified: 1/6/2026
Source: NIST NVD
Note: Verify all details with official vendor sources before applying patches.

Affected Products

misskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskeymisskey : misskey

Remediation Guidance

Executive Summary

View on NIST NVD