Improper Handling of Insufficient Permissions or Privileges in Mastodon - CVE-2025-62176
Published: April 23, 2026
Vulnerability identifier: #VU126983
CSH Severity: Low
CVSS v4: 5.3 [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]
CVE-ID: CVE-2025-62176
CWE-ID: CWE-280
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to disclose sensitive information.
The vulnerability exists due to improper handling of insufficient permissions or privileges in the streaming server when handling subscriptions to public timeline channels using a valid authentication token without the read:statuses scope. A remote user can use such a token to disclose sensitive information.
This only affects newly published public posts on public timelines and may result in unexpected access to public posts in limited-federation deployments.
Affected software
Mastodon
How to mitigate CVE-2025-62176
Install security update from vendor's website.
Mastodon - addressed in versions 4.2.27, 4.3.14, 4.4.6