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.
References
Link | Resource |
---|---|
https://github.com/matrix-org/synapse/commit/03318a766cac9f8b053db2214d9c332a977d226c | Patch Third Party Advisory |
https://github.com/matrix-org/synapse/releases/tag/v1.33.2 | Release Notes Third Party Advisory |
https://github.com/matrix-org/synapse/security/advisories/GHSA-x345-32rc-8h85 | Patch Third Party Advisory |
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/ |
History
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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
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
Redhat Information
No data.