Service interruption via recursive federation messages
Published Dec 4, 2022 · Updated Apr 24, 2025
Uncontrolled recursion in Mastodon 4.0.2 and earlier allows remote attackers to interrupt service through crafted federation activity. The federation workflow repeatedly pulls attacker-generated messages from wildcard-DNS server names, causing Sidekiq queues and the database to grow without a termination bound. Attackers require bot accounts on the target instance and accounts on an attacker-controlled federated server; the resulting resource exhaustion affects availability.
Summary
What happened
Uncontrolled recursion in Mastodon 4.0.2 and earlier allows remote attackers to interrupt service through crafted federation activity. The federation workflow repeatedly pulls attacker-generated messages from wildcard-DNS server names, causing Sidekiq queues and the database to grow without a termination bound. Attackers require bot accounts on the target instance and accounts on an attacker-controlled federated server; the resulting resource exhaustion affects availability.
The record
- CVE
- CVE-2022-46405
- Published
- Dec 4, 2022
- Updated
- Apr 24, 2025
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-674, T1499.003
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Dec 4, 2022CVE publishedPublication date reported by the CVE source.
- Apr 24, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
- Recursive federation queue-exhaustion procedureproof of concept · demonstrated
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Reported exploitation
- Hachyderm recursive federation attackreported exploitation
Technologies
Your stack
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Your stack
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