CVE-2024-31208
Description
Synapse is an open-source Matrix homeserver. A remote Matrix user with malicious intent, sharing a room with Synapse instances before 1.105.1, can dispatch specially crafted events to exploit a weakness in the V2 state resolution algorithm. This can induce high CPU consumption and accumulate excessive data in the database of such instances, resulting in a denial of service. Servers in private federations, or those that do not federate, are not affected. Server administrators should upgrade to 1.105.1 or later. Some workarounds are available. One can ban the malicious users or ACL block servers from the rooms and/or leave the room and purge the room using the admin API.
How to fix
- matrix synapse1.105.1 or later
- matrix-synapse1.105.1 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| matrix synapse | v < 1.105.1 | 1.105.1 |
| fedoraproject fedora | 38, 39, 40 | — |
| matrix-synapsePyPI | v < 1.105.1 | 1.105.1 |
Check your version
Choose the product and enter the version you run to see whether it falls in the affected range.
Attack Surface Management
See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.