Detections
Analytics

SCA: security update for matrix-synapse (GHSA-5wrh-4jwv-5w78)

high Tenable Cloud Security Plugin ID 411063

Description

There are packages installed that are affected by a vulnerability referenced in the following CVE:

 - 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. (CVE-2021-21392)

See Also

https://github.com/advisories/GHSA-5wrh-4jwv-5w78

Plugin Details

Severity: High

ID: 411063

Version: Revision 1.5

Type: Local

Family: SCA Checks

Published: 1/23/2025

Updated: 7/2/2026

Supported Sensors: Tenable Cloud Security, Tenable Self-Hosted Container Security

Risk Information

VPR

Risk Factor: Low

Score: 3.5

Percentile: 51.63

Vendor

Vendor Severity: High

CVSS v2

Risk Factor: Medium

Base Score: 4.9

Temporal Score: 3.6

Vector: CVSS2#AV:N/AC:M/Au:S/C:P/I:P/A:N

CVSS Score Source: CVE-2021-21392

CVSS v3

Risk Factor: Medium

Base Score: 6.3

Temporal Score: 5.5

Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:H/A:N

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

CVSS v4

Risk Factor: High

Base Score: 7.1

Threat Score: 5

Threat Vector: CVSS:4.0/E:U

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N

Vulnerability Information

Exploit Ease: No known exploits are available

Patch Publication Date: 4/13/2021

Vulnerability Publication Date: 4/12/2021

Reference Information

CVE: CVE-2021-21392

cwe: CWE-601