VulnerabilityAnalyzed

CVE-2025-25306

An attacker can forge an object where they claim authority in the `url` field even if the specific ActivityPub object type require authority in the `id` field.

CRITICAL 9.3EPSS 0.18%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.18%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Misskey is an open source, federated social media platform. The patch for CVE-2024-52591 did not sufficiently validate the relation between the `id` and `url` fields of ActivityPub objects. An attacker can forge an object where they claim authority in the `url` field even if the specific ActivityPub object type require authority in the `id` field. Version 2025.2.1 addresses the issue.

CVSS 3.1: 9.3 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:N
EPSS: 0.18% probability · 7th percentile
CISA KEV: Not listed
Weakness: CWE-346, CWE-441, CWE-1025
Affected: misskey/misskey
Source: security-advisories@github.com

References

https://github.com/misskey-dev/misskey/releases/tag/2025.2.1Patch
https://github.com/misskey-dev/misskey/security/advisories/GHSA-6w2c-vf6f-xf26Third Party Advisory

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.