Upstream information
Description
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.SUSE information
Overall state of this security issue: Does not affect SUSE products
This issue is currently rated as having moderate severity.
| CVSS detail | National Vulnerability Database | 
|---|---|
| Base Score | 5 | 
| Vector | AV:N/AC:L/Au:N/C:N/I:N/A:P | 
| Access Vector | Network | 
| Access Complexity | Low | 
| Authentication | None | 
| Confidentiality Impact | None | 
| Integrity Impact | None | 
| Availability Impact | Partial | 
| CVSS detail | National Vulnerability Database | 
|---|---|
| Base Score | 5.3 | 
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L | 
| Attack Vector | Network | 
| Attack Complexity | Low | 
| Privileges Required | None | 
| User Interaction | None | 
| Scope | Unchanged | 
| Confidentiality Impact | None | 
| Integrity Impact | None | 
| Availability Impact | Low | 
| CVSSv3 Version | 3.1 | 
List of released packages
| Product(s) | Fixed package version(s) | References | 
|---|---|---|
| openSUSE Tumbleweed | 
  |  Patchnames:  openSUSE-Tumbleweed-2024-11041  | 
SUSE Timeline for this CVE
CVE page created: Tue May 11 19:51:51 2021CVE page last modified: Sat Nov 1 22:28:19 2025