#VU106268 Origin validation error in Misskey - CVE-2025-25306

Vulnerability identifier: #VU106268

Vulnerability risk: High

CVSSv4.0: 6.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2025-25306

CWE-ID: CWE-346

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Misskey
Web applications / Modules and components for CMS

Vendor: Misskey Development Division

Description

The vulnerability allows a remote attacker to compromise the target system.

The vulnerability exists due to incomplete patch on CVE-2024-52591 (SB2025033119). A remote 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.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Misskey: 2025.1.0 - 2025.2.0

---

External links
https://github.com/misskey-dev/misskey/releases/tag/2025.2.1
https://github.com/misskey-dev/misskey/security/advisories/GHSA-6w2c-vf6f-xf26

---

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.