CVE-2025-66402Published

misskey.js's export data contains private post data

Collected exploitation and prediction evidence

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

cve-program · CVE-2025-66402

Published

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.

Source published: 15 Dec 2025 23:09:57 UTC
Source modified: 16 Dec 2025 15:09:28 UTC
Observed here: 23 Oct 2026 15:48:27 UTC
Source terms: CVE Program Terms of Use

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 4.0 · 7.1 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

euvd · EUVD-2025-203442

Published

EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON.

Original publisher date fields

datePublished: Dec 15, 2025, 11:09:57 PM

dateUpdated: Dec 16, 2025, 3:09:28 PM

Source published: Dec 15, 2025, 11:09:57 PM (timezone not stated)
Source modified: Dec 16, 2025, 3:09:28 PM (timezone not stated)
Observed here: 9 Nov 2026 06:02:42 UTC
Source terms: ENISA EUVD · source terms and attribution apply

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: euvd · ENISA EUVD · source terms and attribution apply. Source text is retained; field grouping and change labels are provided by ChangeIntel.

EUVD CVSS 4.0 · 7.1 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

nvd · CVE-2025-66402

Published

NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON.

Source analysis status: Analyzed

Weakness classifications: CWE-862

Original publisher date fields

published: 2025-12-16T00:16:02.207

lastModified: 2026-10-14T13:10:00.187

37 source CPE criteria · context only

cpe:2.3:a:misskey:misskey:*:*:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:-:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta16:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta21:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta22:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta23:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta24:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta25:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta26:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta27:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta28:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta29:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta30:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta31:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta32:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta33:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta34:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta35:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta36:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta37:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta38:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta39:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta40:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta41:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta42:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:beta43:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:rc1:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:rc10:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:rc11:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:rc2:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:rc3:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:rc4:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:rc5:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:rc6:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:rc7:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:rc8:*:*:*:*:*:*
cpe:2.3:a:misskey:misskey:13.0.0:rc9:*:*:*:*:*:*

The original JSON retains the logical configuration operators, exclusions and version bounds.

Source published: 16 Dec 2025 00:16:02 UTC
Source modified: 14 Oct 2026 13:10:00 UTC
Observed here: 25 Oct 2026 03:17:36 UTC
Source terms: NIST NVD usage terms; underlying source attribution retained

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 4.0 · [email protected] · Secondary · 7.1 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

CVSS 3.1 · [email protected] · Primary · 6.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

osv · GHSA-496g-mmpw-j9x3

Published

### Summary After adding private posts (followers, direct) that you do not have permission to view to your favorites or clips, you can export them to view the contents of the private posts. ### PoC 1. Create an account (X) for testing and an account (Y) for private posts on the same server. 2. Send appropriate content from Y using "Follow" 3. Send appropriate content to any user using "Nominate" from Y 4. Obtain the URLs for the two posts above using Y's account. 5. Query the URLs for the two posts using X and add them to your favorites or clips. 6. Export your favorites or clips using X. 7. Check the exported data. Note: Verified in v2025.11.1 ### Impact This could allow an attacker to view the contents of private posts. If you have pinned private posts, this could be a real problem, as the ID of the private post can be obtained by viewing the user page on the original server.

Source published: 15 Dec 2025 20:55:27 UTC
Source modified: 3 Feb 2026 03:16:36 UTC
Observed here: 24 Oct 2026 13:17:17 UTC
Source terms: GitHub Advisory Database · CC-BY-4.0

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

CVSS_V4 · 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

Publisher rating · HIGH