CVE-2022-24307: Joinmastodon Mastodon

Critical severity, CVSS 9.8. EPSS: 1.4% chance of exploitation in the next 30 days.

Mastodon before 3.3.2 and 3.4.x before 3.4.6 has incorrect access control because it does not compact incoming signed JSON-LD activities. (JSON-LD signing has been supported since version 1.6.0.)

Affected products

• Joinmastodon Mastodon: before 3.3.2 (fixed in 3.3.2); from 3.4.0, before 3.4.6 (fixed in 3.4.6)

Published 2022-02-03. Last modified 2026-06-17.