CVE-2021-21332

MEDIUM

Matrix Synapse < 1.27.0 - XSS

Title source: rule
STIX 2.1

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 password reset endpoint served via Synapse was vulnerable to cross-site scripting (XSS) attacks. The impact depends on the configuration of the domain that Synapse is deployed on, but may allow access to cookies and other browser data, CSRF vulnerabilities, and access to other resources served on the same domain or parent domains. This is fixed in version 1.27.0.

References (5)

Core 5

Scores

CVSS v3 6.9
EPSS 0.0050
EPSS Percentile 66.2%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:L/A:N

Details

CWE
CWE-79
Status published
Products (3)
fedoraproject/fedora 34
matrix/synapse < 1.27.0
pypi/matrix-synapse 0 - 1.27.0PyPI
Published Mar 26, 2021
Tracked Since Feb 18, 2026