CVE-2026-28431
Misskey lacks proper authorization checks and input validationMisskey is an open source, federated social media platform. All Misskey servers running versions 8.45.0 and later, but prior to 2026.3.1, contain a vulnerability that allows bad actors access to data that they ordinarily wouldn't be able to access due to insufficient permission checks and proper input validation. This vulnerability occurs regardless of whether federation is enabled or not. This vulnerability could lead to a significant data breach. This vulnerability is fixed in 2026.3.1.
We have discovered 10 live websites that are affected by CVE-2026-28431.
Affected Software
| Product |  Misskey |
| Category | Message Boards |
| Vulnerable Domains | 10 live websites (100% of Misskey install base) |
| Vulnerable Versions |
|
| Vulnerable Versions Count | 1 versions ( 50% of all versions) |
Common Weakness Enumeration
CWE-285 Improper AuthorizationDetails
- Published - Mar 9, 2026
- Updated - Mar 10, 2026
CVE References
CWE References
CWE
Website Distribution by Country
Number of websites using CVE-2026-28431 United States | 6 websites |
 Germany | 1 websites |
 Japan | 1 websites |
 Russia | 1 websites |
 Singapore | 1 websites |
Website Distribution by TLD
Number of websites using CVE-2026-28431| .io | 2 websites |
| .com | 1 websites |
| .de | 1 websites |
| .ru | 1 websites |
Vulnerable Versions
Vulnerable versions are highlighted in redWebsites affected by CVE-2026-28431
Top websites that are affected by CVE-2026-28431. Please click on the "Contact us" link to get more information.| Domain | Country | Rank | Contacts |
|---|---|---|---|
| *******.io | United States | ***,*** | |
| **.*******.io | United States | *,***,*** | |
| ********.moe | United States | *,***,*** | |
| ******.*************.tech | United States | **,***,*** | |
| **.*******.xyz | United States | **,***,*** | |
| ******.com | United States | **,***,*** | |
| *******.****.de | Germany | **,***,*** | |
| *****.********.red | Singapore | **,***,*** | |
| ********.ru | Russia | **,***,*** | |
| ***.pw | Japan | **,***,*** |
FAQ
CVE-2026-28431 is Improper Authorization in Misskey
A total of 10 websites have been identified as vulnerable to CVE-2026-28431, based on global website indexing conducted by WebTechSurvey.
The Misskey is affected by the CVE-2026-28431 vulnerability.
Misskey versions up to 2026.3.1 are vulnerable to CVE-2026-28431.
CVE-2026-28431 is resolved in version 2026.3.1 of Misskey.