UBUNTU-CVE-2021-29471
See a problem?- Source
- https://ubuntu.com/security/notices/UBUNTU-CVE-2021-29471
- Import Source
- https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-29471.json
- JSON Data
- https://api.osv.dev/v1/vulns/UBUNTU-CVE-2021-29471
- Related
- Published
- 2021-05-11T15:15:00Z
- Modified
- 2021-05-11T15:15:00Z
- Severity
-
- 5.3 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L CVSS Calculator
- Summary
- [none]
- Details
-
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
-
- https://ubuntu.com/security/CVE-2021-29471
- https://github.com/matrix-org/synapse/security/advisories/GHSA-x345-32rc-8h85
- https://github.com/matrix-org/synapse/commit/03318a766cac9f8b053db2214d9c332a977d226c
- https://github.com/matrix-org/synapse/releases/tag/v1.33.2
- https://www.cve.org/CVERecord?id=CVE-2021-29471
Affected packages
Ubuntu:Pro:18.04:LTS / matrix-synapse
Package
- Name
- matrix-synapse
Ubuntu:20.04:LTS / matrix-synapse
Package
- Name
- matrix-synapse
Affected ranges
- Type
- ECOSYSTEM
- Events
-
Introduced0Unknown introduced version / All previous versions are affected