CVE-2025-66402Public exploitNetwork attack vector

Private-post disclosure via unchecked export queries

Published Dec 15, 2025 · Updated Dec 15, 2025

Missing authorization in Misskey 13.0.0-beta.16 through 2025.11.1 allows remote authenticated users to read private posts through data exports. ExportClipsProcessorService and ExportFavoritesProcessorService serialized related notes without applying QueryService.generateVisibilityQuery to the requesting user. Any account that knows a followers-only or direct note URL can add the note to its own favorites or clip and export its contents; pinned posts can expose the needed ID, and the reported impact is read-only disclosure.

CVSS severity7.1
High
EPSS probability0.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authorization in Misskey 13.0.0-beta.16 through 2025.11.1 allows remote authenticated users to read private posts through data exports. ExportClipsProcessorService and ExportFavoritesProcessorService serialized related notes without applying QueryService.generateVisibilityQuery to the requesting user. Any account that knows a followers-only or direct note URL can add the note to its own favorites or clip and export its contents; pinned posts can expose the needed ID, and the reported impact is read-only disclosure.

The record

CVE
CVE-2025-66402
Published
Dec 15, 2025
Updated
Dec 15, 2025
Vendor
Misskey Project
Product
Misskey
Classifications
CWE-862, T1213
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Dec 15, 2025CVE publishedPublication date reported by the CVE source.
  2. Dec 15, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 13.0.0-beta.16, < 2025.12.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Misskey Project · Misskeyversion=>= 13.0.0-beta.16, < 2025.12.0

Published CVSS scores

7.1GitHub, Inc.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
6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-862Missing Authorization
T1213Data from Information Repositories

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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