CVE-2021-21392

Published Apr 12, 2021

Last updated a year ago

Overview

Description
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.
Source
security-advisories@github.com
NVD status
Modified

Social media

Hype score
Not currently trending

Risk scores

CVSS 3.1

Type
Primary
Base score
6.3
Impact score
4.2
Exploitability score
2.1
Vector string
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:H/A:N
Severity
MEDIUM

CVSS 2.0

Type
Primary
Base score
4.9
Impact score
4.9
Exploitability score
6.8
Vector string
AV:N/AC:M/Au:S/C:P/I:P/A:N

Weaknesses

nvd@nist.gov
CWE-601
security-advisories@github.com
CWE-601

Configurations