CVE-2021-39164

Published Aug 31, 2021

Last updated a year ago

Overview

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.
Source
security-advisories@github.com
NVD status
Modified

Risk scores

CVSS 3.1

Type
Primary
Base score
3.1
Impact score
1.4
Exploitability score
1.6
Vector string
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
Severity
LOW

CVSS 2.0

Type
Primary
Base score
3.5
Impact score
2.9
Exploitability score
6.8
Vector string
AV:N/AC:M/Au:S/C:P/I:N/A:N

Weaknesses

security-advisories@github.com
CWE-200
nvd@nist.gov
CWE-863

Social media

Hype score
Not currently trending

Configurations