Authorization bypass through user-controlled key in Misskey - CVE-2026-28433
Published: April 28, 2026
Vulnerability identifier: #VU128342
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-28433
CWE-ID: CWE-639
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Misskey Development Division
Affected software:
Misskey
Misskey
Detailed vulnerability description
The vulnerability allows a remote user to disclose sensitive information.
The vulnerability exists due to authorization bypass through a user-controlled key in the import function when importing data by file ID. A remote user can supply the ID corresponding to another user's file to disclose sensitive information.
Exploitation requires knowledge of the ID corresponding to the target file.
How to mitigate CVE-2026-28433
Install security update from vendor's website.