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.
Advisories
Source ID Title
EUVD EUVD EUVD-2021-0128 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.
Github GHSA Github GHSA GHSA-5wrh-4jwv-5w78 Open redirect via transitional IPv6 addresses on dual-stack networks
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

No history.

cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2024-08-03T18:09:15.930Z

Reserved: 2020-12-22T00:00:00

Link: CVE-2021-21392

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Modified

Published: 2021-04-12T22:15:13.147

Modified: 2024-11-21T05:48:15.877

Link: CVE-2021-21392

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.