UBUNTU-CVE-2021-21274
- Source
- https://ubuntu.com/security/CVE-2021-21274
- Import Source
- https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-21274.json
- JSON Data
- https://api.test.osv.dev/v1/vulns/UBUNTU-CVE-2021-21274
- Related
- Published
- 2021-02-26T18:15:00Z
- Modified
- 2024-10-15T14:08:00Z
- Severity
-
- 6.5 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H 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 1.25.0, a malicious homeserver could redirect requests to their .well-known file to a large file. This can lead to a denial of service attack where homeservers will consume significantly more resources when requesting the .well-known file of a malicious homeserver. This affects any server which accepts federation requests from untrusted servers. Issue is resolved in version 1.25.0. As a workaround the
federation_domain_whitelistsetting can be used to restrict the homeservers communicated with over federation. - References
-
- https://ubuntu.com/security/CVE-2021-21274
- https://github.com/matrix-org/synapse/security/advisories/GHSA-2hwx-mjrm-v3g8
- https://github.com/matrix-org/synapse/commit/ff5c4da1289cb5e097902b3e55b771be342c29d6
- https://github.com/matrix-org/synapse/pull/8950
- https://github.com/matrix-org/synapse/releases/tag/v1.25.0
- https://www.cve.org/CVERecord?id=CVE-2021-21274
Affected packages
Ubuntu:Pro:18.04:LTS / matrix-synapse
Package
- Name
- matrix-synapse
- Purl
- pkg:deb/ubuntu/matrix-synapse?arch=src?distro=esm-apps/bionic
Ubuntu:20.04:LTS / matrix-synapse
Package
- Name
- matrix-synapse
- Purl
- pkg:deb/ubuntu/matrix-synapse?arch=src?distro=focal
Affected ranges
- Type
- ECOSYSTEM
- Events
-
Introduced0Unknown introduced version / All previous versions are affected