How severe is CVE-2025-66402?

CVE-2025-66402 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2025-66402 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-66402?

CVE-2025-66402 primarily affects Misskey. In total, 37 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-66402?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2025-66402 have an EU (EUVD) identifier?

Yes. CVE-2025-66402 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-203442.

When was CVE-2025-66402 published?

CVE-2025-66402 was published on 2025-12-16 and last updated on 2026-06-17.

CVE-2025-66402

CVE-2025-66402 is a medium-severity vulnerability in Misskey with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-862.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v4: 7.1
EPSS exploit prediction: 0% (18th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-203442
Weakness: CWE-862
Affected product: Misskey
Published: 2025-12-16
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2025-66402?: 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.
How severe is CVE-2025-66402?: CVE-2025-66402 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2025-66402 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-66402?: CVE-2025-66402 primarily affects Misskey. In total, 37 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-66402?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-66402 have an EU (EUVD) identifier?: Yes. CVE-2025-66402 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-203442.
When was CVE-2025-66402 published?: CVE-2025-66402 was published on 2025-12-16 and last updated on 2026-06-17.

References

Affected products (37)

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:*:*:*:*:*:*

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