GHSA-jj53-8fmw-f2w2

Suggest an improvement
Source
https://github.com/advisories/GHSA-jj53-8fmw-f2w2
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2021/09/GHSA-jj53-8fmw-f2w2/GHSA-jj53-8fmw-f2w2.json
JSON Data
https://api.test.osv.dev/v1/vulns/GHSA-jj53-8fmw-f2w2
Aliases
Published
2021-09-01T18:25:44Z
Modified
2026-05-07T05:03:16Z
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
  • 2.3 (Low) CVSS_V4 - CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N CVSS Calculator
Summary
Adding a private/unlisted room to a community exposes room metadata in an unauthorised manner.
Details

Impact

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.

Patches

Server administrators should upgrade to 1.41.1 or higher.

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 following endpoints:

  • /_matrix/client/r0/groups/{group_id}/rooms
  • /_matrix/client/unstable/groups/{group_id}/rooms

References

n/a

For more information

If you have any questions or comments about this advisory, e-mail us at security@matrix.org.

Database specific 
{
    "cwe_ids": [
        "CWE-200"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2021-08-31T17:46:08Z",
    "nvd_published_at": "2021-08-31T16:15:00Z",
    "severity": "LOW"
}
References

Affected packages

PyPI / matrix-synapse

Package

Name
matrix-synapse
View open source insights on deps.dev
Purl
pkg:pypi/matrix-synapse

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
1.41.1

Affected versions

0.*
0.33.5
0.33.5.1
0.33.6rc1
0.33.6
0.33.7rc1
0.33.7rc2
0.33.7
0.33.8rc2
0.33.8
0.33.9
0.34.0rc1
0.34.0rc2
0.34.0
0.34.0.1
0.34.1.1
0.99.0rc1
0.99.0rc2
0.99.0rc3
0.99.0rc4
0.99.0
0.99.1rc1
0.99.1rc2
0.99.1
0.99.1.1
0.99.2rc1
0.99.2
0.99.3rc1
0.99.3
0.99.3.1
0.99.3.2
0.99.4rc1
0.99.4
0.99.5rc1
0.99.5
0.99.5.1
0.99.5.2
1.*
1.0.0rc1
1.0.0rc2
1.0.0rc3
1.0.0
1.1.0rc1
1.1.0rc2
1.1.0
1.2.0rc1
1.2.0rc2
1.2.0
1.2.1
1.3.0rc1
1.3.0
1.3.1
1.4.0rc1
1.4.0rc2
1.4.0
1.4.1rc1
1.4.1
1.5.0rc1
1.5.0rc2
1.5.0
1.5.1
1.6.0rc1
1.6.0rc2
1.6.0
1.6.1
1.7.0rc1
1.7.0rc2
1.7.0
1.7.1
1.7.2
1.7.3
1.8.0rc1
1.8.0
1.9.0.dev1
1.9.0.dev2
1.9.0rc1
1.9.0
1.9.1
1.10.0rc1
1.10.0rc2
1.10.0rc3
1.10.0rc5
1.10.0
1.10.1
1.11.0rc1
1.11.0
1.11.1
1.12.0rc1
1.12.0
1.12.1rc1
1.12.1
1.12.2
1.12.3
1.12.4rc1
1.12.4
1.13.0rc1
1.13.0rc2
1.13.0rc3
1.13.0
1.14.0rc1
1.14.0rc2
1.14.0
1.15.0rc1
1.15.0
1.15.1
1.15.2
1.16.0rc1
1.16.0rc2
1.16.0
1.16.1
1.17.0rc1
1.17.0
1.18.0rc1
1.18.0rc2
1.18.0
1.19.0rc1
1.19.0
1.19.1rc1
1.19.1
1.19.2
1.19.3
1.20.0rc1
1.20.0rc2
1.20.0rc3
1.20.0rc4
1.20.0rc5
1.20.0
1.20.1
1.21.0rc1
1.21.0rc2
1.21.0rc3
1.21.0
1.21.1
1.21.2
1.22.0rc1
1.22.0rc2
1.22.0
1.22.1
1.23.0rc1
1.23.0
1.23.1
1.24.0rc1
1.24.0rc2
1.24.0
1.25.0rc1
1.25.0
1.26.0rc1
1.26.0rc2
1.26.0
1.27.0rc1
1.27.0rc2
1.27.0
1.28.0rc1
1.28.0
1.29.0rc1
1.29.0
1.30.0rc1
1.30.0
1.30.1
1.31.0rc1
1.31.0
1.32.0rc1
1.32.0
1.32.1
1.32.2
1.33.0rc1
1.33.0rc2
1.33.0
1.33.1
1.33.2
1.34.0rc1
1.34.0
1.35.0rc1
1.35.0rc2
1.35.0rc3
1.35.0
1.35.1
1.36.0rc1
1.36.0rc2
1.36.0
1.37.0rc1
1.37.0
1.37.1rc1
1.37.1
1.38.0rc1
1.38.0rc2
1.38.0rc3
1.38.0
1.38.1
1.39.0rc1
1.39.0rc2
1.39.0rc3
1.39.0
1.40.0rc1
1.40.0rc2
1.40.0rc3
1.40.0
1.41.0rc1
1.41.0

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2021/09/GHSA-jj53-8fmw-f2w2/GHSA-jj53-8fmw-f2w2.json"