SB20240704106 - Multiple vulnerabilities in Mastodon



SB20240704106 - Multiple vulnerabilities in Mastodon

Published: July 4, 2024 Updated: April 23, 2026

Security Bulletin ID SB20240704106
CSH Severity
High
Patch available
YES
Number of vulnerabilities 3
Exploitation vector Remote access
Highest impact Data manipulation

Breakdown by Severity

High 33% Medium 33% Low 33%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 3 secuirty vulnerabilities.


1) Improper access control (CVE-ID: N/A)

The vulnerability allows a remote attacker to disclose sensitive information.

The vulnerability exists due to improper access control in multiple API endpoints when handling requests with application tokens. A remote attacker can send requests using application tokens to disclose sensitive information.

On affected configurations, unregistered users can access hashtag timelines that should not be publicly accessible, and applications can access the public timeline regardless of their permissions.


2) Improper access control (CVE-ID: CVE-2024-37903)

The vulnerability allows a remote attacker to disclose sensitive information.

The vulnerability exists due to improper access control in audience extension handling for existing posts when processing crafted activities. A remote attacker can send specific crafted activities to disclose sensitive information.

Exploitation requires knowledge of the protocol identifier for the target message and control of an account on a Mastodon server that already has legitimate access to that message.


3) Insufficient Session Expiration (CVE-ID: N/A)

The vulnerability allows a remote user to disclose sensitive information.

The vulnerability exists due to insufficient session expiration in the streaming API when maintaining WebSocket streaming connections after an access token is revoked. A remote user can keep an existing streaming connection open and continue subscribing to streamable timelines to disclose sensitive information.

User interaction is required because the user must first authorize the application before revoking its access token.


Remediation

Install update from vendor's website.