Synapse's V2 state resolution weakness allows DoS from remote room members
Summary
Synapse's V2 state resolution weakness allows DoS from remote room members
Original description
The description as published by the source.
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.
Source: OSV.dev (Open Source Vulnerabilities) NVD GitHub Advisory OSV
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2024-31208 matrix-synapse Fixed in: 1.103.0-2
- Ubuntu UBUNTU-CVE-2024-31208 synapse
References
- advisory github.com
- advisory github.com
- advisory nvd.nist.gov
- patch github.com
- web github.com
- web lists.fedoraproject.org
- web lists.fedoraproject.org
- web lists.fedoraproject.org