Detections
Analytics

SCA: security update for matrix-synapse (GHSA-x345-32rc-8h85)

medium Tenable Self-Hosted Container Security Plugin ID 420239

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 1.33.2 "Push rules" can
 specify conditions under which they will match, including `event_match`, which matches event content
 against a pattern including wildcards. Certain patterns can cause very poor performance in the matching
 engine, leading to a denial-of-service when processing moderate length events. The issue is patched in
 version 1.33.2. A potential workaround might be to prevent users from making custom push rules, by
 blocking such requests at a reverse-proxy. (CVE-2021-29471)

See Also

https://github.com/advisories/GHSA-x345-32rc-8h85

Plugin Details

Severity: Medium

ID: 420239

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: 1.2

Percentile: 0.01

Vendor

Vendor Severity: Medium

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 3.7

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

CVSS Score Source: CVE-2021-29471

CVSS v3

Risk Factor: Medium

Base Score: 5.3

Temporal Score: 4.6

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

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

CVSS v4

Risk Factor: Medium

Base Score: 6.3

Threat Score: 1.7

Threat Vector: CVSS:4.0/E:U

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

Vulnerability Information

Exploit Ease: No known exploits are available

Patch Publication Date: 5/13/2021

Vulnerability Publication Date: 5/11/2021

Reference Information

CVE: CVE-2021-29471