What is the CVSS score of CVE-2026-28433?

CVE-2026-28433 has a CVSS 3.1 base score of 4.3 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N. EPSS exploitation probability: 0.0%.

Which versions of Misskey are affected by CVE-2026-28433?

Organizations using Misskey should be aware of moderate risk from CVE-2026-28433, a IDOR vulnerability rated CVSS 4.3. Exploitation could compromise the security of affected deployments.

How to fix or mitigate CVE-2026-28433?

Within 30 days: Identify affected systems and apply vendor patches as part of regular patch cycle. Monitor vendor channels for patch availability.

Misskey CVE-2026-28433

MEDIUM

Authorization Bypass Through User-Controlled Key (CWE-639)

2026-03-10 security-advisories@github.com

Authentication Bypass Misskey

4.3

CVSS 3.1 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

4.3 MEDIUM

AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

Primary rating from GitHub Advisory · only source for this CVE.

CVSS VectorGitHub Advisory

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

None

Lifecycle Timeline

Analysis Generated

Mar 12, 2026 - 21:55 vuln.today

CVE Published

Mar 10, 2026 - 07:43 nvd

MEDIUM 4.3

DescriptionGitHub Advisory

Misskey is an open source, federated social media platform. All Misskey servers running versions 10.93.0 and later, but prior to 2026.3.1, contain a vulnerability that allows importing other users' data due to lack of ownership validation. The impact of this vulnerability is estimated to be relatively low, as bad actors would require the ID corresponding to the target file for import. This vulnerability is fixed in 2026.3.1.

AnalysisAI

Misskey versions 10.93.0 through 2026.3.0 allow authenticated users to import arbitrary user data due to insufficient ownership validation, enabling attackers with knowledge of target file IDs to access other users' information. The vulnerability requires valid login credentials and knowledge of specific file identifiers, limiting its practical impact. No patch is currently available.

Technical ContextAI

Classified as CWE-639 (Authorization Bypass Through User-Controlled Key). Affects but. Misskey is an open source, federated social media platform. All Misskey servers running versions 10.93.0 and later, but prior to 2026.3.1, contain a vulnerability that allows importing other users' data due to lack of ownership validation. The impact of this vulnerability is estimated to be relatively low, as bad actors would require the ID corresponding to the target file for import. This vulnerability is fixed in 2026.3.1.