CVE-2021-21392

Published: 12 April 2021

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 1.28.0 requests to user provided domains were not restricted to external IP addresses when transitional IPv6 addresses were used. Outbound requests to federation, identity servers, when calculating the key validity for third-party invite events, sending push notifications, and generating URL previews are affected. This could cause Synapse to make requests to internal infrastructure on dual-stack networks. See referenced GitHub security advisory for details and workarounds.

Priority

Medium

CVSS 3 base score: 6.3

Status

Package Release Status
matrix-synapse
Launchpad, Ubuntu, Debian
Upstream
Released (1.28.0-1)
Ubuntu 21.10 (Impish Indri) Needed

Ubuntu 21.04 (Hirsute Hippo) Needed

Ubuntu 20.04 LTS (Focal Fossa) Needed

Ubuntu 18.04 LTS (Bionic Beaver) Needed

Ubuntu 16.04 ESM (Xenial Xerus) Does not exist

Ubuntu 14.04 ESM (Trusty Tahr) Does not exist