CVE-2023-52139: Misskey vulnerable to improper authorization when accessing with third-party application

Severity: critical (CVSS 9.6 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-12-29 · updated 2026-06-17
Weakness: CWE-285

Description

Misskey is an open source, decentralized social media platform. Third-party applications may be able to access some endpoints or Websocket APIs that are incorrectly specified as [kind](https://github.com/misskey-dev/misskey/blob/406b4bdbe79b5b0b68fcdcb3c4b6e419460a0258/packages/backend/src/server/api/endpoints.ts#L811) or [secure](https://github.com/misskey-dev/misskey/blob/406b4bdbe79b5b0b68fcdcb3c4b6e419460a0258/packages/backend/src/server/api/endpoints.ts#L805) without the user's permission and perform operations such as reading or adding non-public content. As a result, if the user who authenticated the application is an administrator, confidential information such as object storage secret keys and SMTP server passwords will be leaked, and general users can also create invitation codes without permission and leak non-public user information. This is patched in version [2023.12.1](https://github.com/misskey-dev/misskey/commit/c96bc36fedc804dc840ea791a9355d7df0748e64).

Affected products

misskey-dev misskey: before 2023.12.1 — fixed in 2023.12.1

How to fix

Upgrade to a fixed version: misskey-dev misskey 2023.12.1. Check the vendor advisory for mitigations.

References

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