CVE-2021-21273 Detail

Current 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 1.25.0, requests to user provided domains were not restricted to external IP addresses when calculating the key validity for third-party invite events and sending push notifications. This could cause Synapse to make requests to internal infrastructure. The type of request was not controlled by the user, although limited modification of request bodies was possible. For the most thorough protection server administrators should remove the deprecated `federation_ip_range_blacklist` from their settings after upgrading to Synapse v1.25.0 which will result in Synapse using the improved default IP address restrictions. See the new `ip_range_blacklist` and `ip_range_whitelist` settings if more specific control is necessary.


View Analysis Description

Severity



CVSS 3.x Severity and Metrics:

NIST CVSS score
NIST: NVD
Base Score:  6.1 MEDIUM
Vector:  CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Nist CVSS score does not match with CNA score
CNA:  GitHub, Inc.
Base Score:  3.1 LOW
Vector:  CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N


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: It is possible that the NVD CVSS may not match that of the CNA. The most common reason for this is that publicly available information does not provide sufficient detail or that information simply was not available at the time the CVSS vector string was assigned.

References to Advisories, Solutions, and Tools

By selecting these links, you will be leaving NIST webspace. We have provided these links to other web sites because they may have information that would be of interest to you. No inferences should be drawn on account of other sites being referenced, or not, from this page. There may be other web sites that are more appropriate for your purpose. NIST does not necessarily endorse the views expressed, or concur with the facts presented on these sites. Further, NIST does not endorse any commercial products that may be mentioned on these sites. Please address comments about this page to nvd@nist.gov.

Hyperlink Resource
https://github.com/matrix-org/synapse/commit/30fba6210834a4ecd91badf0c8f3eb278b72e746 Patch  Third Party Advisory 
https://github.com/matrix-org/synapse/pull/8821 Patch  Third Party Advisory 
https://github.com/matrix-org/synapse/releases/tag/v1.25.0 Third Party Advisory 
https://github.com/matrix-org/synapse/security/advisories/GHSA-v936-j8gp-9q3p Patch  Third Party Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-601 URL Redirection to Untrusted Site ('Open Redirect') Provider acceptance level GitHub, Inc.  

Known Affected Software Configurations Switch to CPE 2.2

CPEs loading, please wait.

Denotes Vulnerable Software
Are we missing a CPE here? Please let us know.

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2021-21273
NVD Published Date:
02/26/2021
NVD Last Modified:
03/05/2021
Source:
GitHub, Inc.