CVE-2021-39164

 

Published at: - 31-08-2021 07:15

Last modified: - 25-10-2022 08:04

Total changes: - 8

Description

Matrix is an ecosystem for open federated Instant Messaging and Voice over IP. In versions 1.41.0 and prior, unauthorised users can access the membership (list of members, with their display names) of a room if they know the ID of the room. The vulnerability is limited to rooms with `shared` history visibility. Furthermore, the unauthorised user must be using an account on a vulnerable homeserver that is in the room. Server administrators should upgrade to 1.41.1 or later in order to receive the patch. One workaround is available. Administrators of servers that use a reverse proxy could, with potentially unacceptable loss of functionality, block the endpoints: `/_matrix/client/r0/rooms/{room_id}/members` with `at` query parameter, and `/_matrix/client/unstable/rooms/{room_id}/members` with `at` query parameter.

Common Vulnerability Scoring System (CVSS)

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N

 

Verification logic

 

Reference

• https://github.com/matrix-org/synapse/security/advisories/GHSA-3x4c-pq33-4w3q
• https://github.com/matrix-org/synapse/releases/tag/v1.41.1
• https://github.com/matrix-org/synapse/commit/cb35df940a
• FEDORA-2021-2e8ed15b14-Mailing List, Third Party Advisory
• FEDORA-2021-f12fdca1bf-Mailing List, Third Party Advisory

 

Keywords

NVD

 

CVE-2021-39164

 

CVE

 

Common vulnerabilities & exposures

 

CVSS

 

Common vulnerability scoring system

 

Security

 

Vulnerabilities

 

Exposures