CVE-2021-39163

Source
https://cve.org/CVERecord?id=CVE-2021-39163
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-39163.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2021-39163
Aliases
Downstream
Related
Published
2021-08-31T16:15:07.950Z
Modified
2026-04-10T04:37:00.689859Z
Severity
  • 3.1 (Low) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N CVSS Calculator
Summary
[none]
Details

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 name, avatar, topic and number of members of a room if they know the ID of the room. This vulnerability is limited to homeservers where the vulnerable homeserver is in the room and untrusted users are permitted to create groups (communities). By default, only homeserver administrators can create groups. However, homeserver administrators can already access this information in the database or using the admin API. As a result, only homeservers where the configuration setting enable_group_creation has been set to true are impacted. Server administrators should upgrade to 1.41.1 or higher to patch the vulnerability. There are two potential workarounds. Server administrators can set enable_group_creation to false in their homeserver configuration (this is the default value) to prevent creation of groups by non-administrators. Administrators that are using a reverse proxy could, with partial loss of group functionality, block the endpoints /_matrix/client/r0/groups/{group_id}/rooms and /_matrix/client/unstable/groups/{group_id}/rooms.

References

Affected packages

Git / github.com/matrix-org/synapse

Affected ranges

Type
GIT
Repo
https://github.com/matrix-org/synapse
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
Fixed
Database specific
{
    "versions": [
        {
            "introduced": "0"
        },
        {
            "fixed": "1.41.1"
        }
    ]
}

Affected versions

Other
hhs-1
hhs-2
hhs-3
hhs-5
hhs-6
hhs-7
hhs-8
v0.*
v0.10.0
v0.10.0-r1
v0.10.0-r2
v0.11.0
v0.11.0-r1
v0.11.0-r2
v0.11.1
v0.12.0
v0.13.1
v0.13.2
v0.13.3
v0.14.0
v0.16.0
v0.16.1
v0.16.1-r1
v0.17.0
v0.17.1
v0.17.2
v0.17.3
v0.18.0
v0.18.1
v0.18.2
v0.18.3
v0.18.4
v0.18.5
v0.2.0
v0.2.1
v0.2.1a
v0.2.2
v0.23.0-rc1
v0.23.0-rc2
v0.25.0-rc1
v0.28.0-rc1
v0.3.0
v0.3.3
v0.3.4
v0.32.0
v0.32.0rc1
v0.32.2
v0.4.1
v0.4.2
v0.5.0
v0.5.1
v0.5.2
v0.5.3
v0.5.3a
v0.5.3b
v0.5.3c
v0.5.4
v0.5.4a
v0.6.0
v0.6.0a
v0.6.0b
v0.6.1
v0.6.1a
v0.6.1b
v0.6.1c
v0.6.1d
v0.6.1e
v0.6.1f
v0.7.0
v0.7.0a
v0.7.0b
v0.7.0c
v0.7.0d
v0.7.0e
v0.7.0f
v0.7.1
v0.7.1-r1
v0.7.1-r2
v0.7.1-r3
v0.7.1-r4
v0.8.0
v0.8.1
v0.8.1-r1
v0.8.1-r2
v0.8.1-r3
v0.8.1-r4
v0.9.0
v0.9.0-r1
v0.9.0-r2
v0.9.0-r3
v0.9.0-r4
v0.9.0-r5
v0.9.1
v0.9.2
v0.9.2-r1
v0.9.2-r2
v0.9.3
v0.99.1rc1
v0.99.2rc1
v0.99.4rc1
v0.99.5.1.dev0
v1.*
v1.1.0rc1
v1.1.0rc2
v1.10.0rc1
v1.11.0rc1
v1.12.0rc1
v1.14.0rc1
v1.15.0rc1
v1.16.0rc1
v1.17.0rc1
v1.18.0rc1
v1.23.0rc1
v1.24.0rc1
v1.27.0rc1
v1.29.0rc1
v1.3.0rc1
v1.30.0rc1
v1.31.0rc1
v1.32.0rc1
v1.34.0rc1
v1.35.0rc1
v1.36.0rc1
v1.4.0rc1
v1.40.0rc1
v1.41.0
v1.41.0rc1
v1.5.0rc1
v1.6.0rc1
v1.8.0rc1
v1.9.0.dev1
v1.9.0.dev2
v1.9.0rc1

Database specific

source
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-39163.json"
unresolved_ranges
[
    {
        "events": [
            {
                "introduced": "0"
            },
            {
                "last_affected": "34"
            }
        ]
    },
    {
        "events": [
            {
                "introduced": "0"
            },
            {
                "last_affected": "35"
            }
        ]
    }
]