Medium severity · published Dec 15, 2025
CVE-2025-66402
misskey.js's export data contains private post data
6.5
CVSS
0.3%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 24% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MI
misskey · misskey-dev
>= 13.0.0-beta.16, < 2025.12.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-66402
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-66402
Patch
https://github.com/misskey-dev/misskey/commit/dc77d59f8712d3fe0b73cd4af2035133839cd57b
Exploit
https://github.com/misskey-dev/misskey/security/advisories/GHSA-496g-mmpw-j9x3
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