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/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://github.com/matrix-org/synapse/commit/03318a766cac9f8b053db2214d9c332a977d226c | Patch Third Party Advisory |
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/ | Mailing List Third Party Advisory |
Information
Published : 2021-05-11 08:15
Updated : 2022-04-05 11:06
NVD link : CVE-2021-29471
Mitre link : CVE-2021-29471
JSON object : View
CWE
CWE-331
Insufficient Entropy
Products Affected
matrix
- synapse
fedoraproject
- fedora