CVE-2026-48115: CWE-285: Improper Authorization in misskey-dev misskey
Misskey is an open source, federated social media platform. All Misskey servers running versions 2024.5.0 and later, but prior to 2026.5.4, contain a vulnerability in the Server Announcements API where insufficient permission checks allow attackers to access limited portions of data that they normally couldn't view. This vulnerability occurs whether or not federation is enabled. This issue has been fixed in version 2026.5.4.
AI Analysis
Technical Summary
Misskey, an open source federated social media platform, contains a CWE-285 improper authorization vulnerability in its Server Announcements API in all versions starting from 2024.5.0 up to 2026.5.4. The vulnerability permits unauthorized attackers to access restricted portions of data that should be protected by permission checks. This issue affects both federated and non-federated deployments. The vulnerability has been resolved in version 2026.5.4.
Potential Impact
Attackers without proper permissions can access limited data that should be restricted, potentially exposing sensitive information. The vulnerability does not require user interaction and can be exploited remotely over the network. The CVSS 4.0 base score is 6.3 (medium severity), reflecting the moderate impact of unauthorized data disclosure without integrity or availability impact.
Mitigation Recommendations
Upgrade affected Misskey instances to version 2026.5.4 or later, where the improper authorization vulnerability in the Server Announcements API has been fixed. No other mitigation or temporary workaround is documented.
CVE-2026-48115: CWE-285: Improper Authorization in misskey-dev misskey
Description
Misskey is an open source, federated social media platform. All Misskey servers running versions 2024.5.0 and later, but prior to 2026.5.4, contain a vulnerability in the Server Announcements API where insufficient permission checks allow attackers to access limited portions of data that they normally couldn't view. This vulnerability occurs whether or not federation is enabled. This issue has been fixed in version 2026.5.4.
CVSS v4.0
Score 6.3medium
Affected software
misskey-dev
misskey
pkg:github/misskey-dev/misskeyRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Misskey, an open source federated social media platform, contains a CWE-285 improper authorization vulnerability in its Server Announcements API in all versions starting from 2024.5.0 up to 2026.5.4. The vulnerability permits unauthorized attackers to access restricted portions of data that should be protected by permission checks. This issue affects both federated and non-federated deployments. The vulnerability has been resolved in version 2026.5.4.
Potential Impact
Attackers without proper permissions can access limited data that should be restricted, potentially exposing sensitive information. The vulnerability does not require user interaction and can be exploited remotely over the network. The CVSS 4.0 base score is 6.3 (medium severity), reflecting the moderate impact of unauthorized data disclosure without integrity or availability impact.
Mitigation Recommendations
Upgrade affected Misskey instances to version 2026.5.4 or later, where the improper authorization vulnerability in the Server Announcements API has been fixed. No other mitigation or temporary workaround is documented.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-05-20T18:46:58.289Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6a710cc4bf32cb7a3449086f
Added to database: 08/03/2026, 21:48:52 UTC
Last enriched: 08/11/2026, 17:54:13 UTC
Last updated: 09/17/2026, 22:01:35 UTC
Views: 49
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