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NOTICE UPDATED - April, 25th 2024

NIST has updated the NVD program announcement page with additional information regarding recent concerns and the temporary delays in enrichment efforts.

CVE-2021-21333 Detail

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.


Severity



CVSS 4.0 Severity and Metrics:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.


NVD Analysts use publicly available information to associate vector strings and CVSS scores. We also display any CVSS information provided within the CVE List from the CNA.

Note: NVD Analysts have not published a CVSS score for this CVE at this time. NVD Analysts use publicly available information at the time of analysis to associate CVSS vector strings.

References to Advisories, Solutions, and Tools

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Hyperlink Resource
https://github.com/matrix-org/synapse/commit/e54746bdf7d5c831eabe4dcea76a7626f1de73df Patch  Third Party Advisory 
https://github.com/matrix-org/synapse/pull/9200 Patch  Third Party Advisory 
https://github.com/matrix-org/synapse/releases/tag/v1.27.0 Third Party Advisory 
https://github.com/matrix-org/synapse/security/advisories/GHSA-c5f8-35qr-q4fm Patch  Third Party Advisory 
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/

Weakness Enumeration

CWE-ID CWE Name Source
CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') cwe source acceptance level NIST  
CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') Contributor acceptance level GitHub, Inc.  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

6 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2021-21333
NVD Published Date:
03/26/2021
NVD Last Modified:
11/06/2023
Source:
GitHub, Inc.