Upstream information

CVE-2021-21333 at MITRE

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 1.27.0, the notification emails sent for notifications for missed messages or for an expiring account are subject to HTML injection. In the case of the notification for missed messages, this could allow an attacker to insert forged content into the email. The account expiry feature is not enabled by default and the HTML injection is not controllable by an attacker. This is fixed in version 1.27.0.

SUSE information

Overall state of this security issue: Does not affect SUSE products

This issue is currently rated as having moderate severity.

CVSS v2 Scores
  National Vulnerability Database
Base Score 2.6
Vector AV:N/AC:H/Au:N/C:N/I:P/A:N
Access Vector Network
Access Complexity High
Authentication None
Confidentiality Impact None
Integrity Impact Partial
Availability Impact None
CVSS v3 Scores
  National Vulnerability Database
Base Score 6.1
Vector CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:N/I:H/A:N
Access Vector Network
Access Complexity High
Privileges Required None
User Interaction Required
Scope Changed
Confidentiality Impact None
Integrity Impact High
Availability Impact None
CVSSv3 Version 3.1
SUSE Bugzilla entry: 1184872 [NEW]

No SUSE Security Announcements cross referenced.