Synapse is a Matrix reference homeserver written in python (pypi package matrix-synapse). Matrix is an ecosystem for open federated Instant Messaging and VoIP. In Synapse before version 1.33.2 "Push rules" can specify conditions under which they will match, including `event_match`, which matches event content against a pattern including wildcards. Certain patterns can cause very poor performance in the matching engine, leading to a denial-of-service when processing moderate length events. The issue is patched in version 1.33.2. A potential workaround might be to prevent users from making custom push rules, by blocking such requests at a reverse-proxy.
History

No history.

cve-icon MITRE Information

Status: PUBLISHED

Assigner: GitHub_M

Published: 2021-05-11T15:05:12

Updated: 2021-08-02T02:06:25

Reserved: 2021-03-30T00:00:00


Link: CVE-2021-29471

JSON object: View

cve-icon NVD Information

Status : Modified

Published: 2021-05-11T15:15:08.507

Modified: 2023-11-07T03:32:37.617


Link: CVE-2021-29471

JSON object: View

cve-icon Redhat Information

No data.