CVE-2021-39163
published 2021-08-31CVE-2021-39163: 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…
PriorityP414low3.1CVSS 3.1
AVNACHPRLUINSUCLINAN
EPSS
0.89%
55.5th percentile
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`.
Affected
5 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | matrix-synapse | < matrix-synapse 1.41.1-1 (forky) | matrix-synapse 1.41.1-1 (forky) |
| fedoraproject | fedora | — | — |
| fedoraproject | fedora | — | — |
| matrix-org | synapse | < 1.41.1 | 1.41.1 |
| matrix | synapse | < 1.41.1 | 1.41.1 |
CVSS provenance
nvdv3.13.1LOWCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
nvdv2.03.5LOWAV:N/AC:M/Au:S/C:P/I:N/A:N
osv3.1LOW
vendor_debian3.1LOW
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OSV
Adding a private/unlisted room to a community exposes room metadata in an unauthorised manner.
osv·2021-09-01
CVE-2021-39163 [LOW] Adding a private/unlisted room to a community exposes room metadata in an unauthorised manner.
Adding a private/unlisted room to a community exposes room metadata in an unauthorised manner.
### 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
GHSA
Adding a private/unlisted room to a community exposes room metadata in an unauthorised manner.
ghsa·2021-09-01
CVE-2021-39163 [LOW] CWE-200 Adding a private/unlisted room to a community exposes room metadata in an unauthorised manner.
Adding a private/unlisted room to a community exposes room metadata in an unauthorised manner.
### 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
OSV
CVE-2021-39163: Matrix is an ecosystem for open federated Instant Messaging and Voice over IP
osv·2021-08-31·CVSS 3.1
CVE-2021-39163 [LOW] CVE-2021-39163: Matrix is an ecosystem for open federated Instant Messaging and Voice over IP
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 workaroun
Debian
CVE-2021-39163: matrix-synapse - Matrix is an ecosystem for open federated Instant Messaging and Voice over IP. I...
vendor_debian·2021·CVSS 3.1
CVE-2021-39163 [LOW] CVE-2021-39163: matrix-synapse - Matrix is an ecosystem for open federated Instant Messaging and Voice over IP. I...
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 workaroun
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
https://github.com/matrix-org/synapse/commit/cb35df940ahttps://github.com/matrix-org/synapse/releases/tag/v1.41.1https://github.com/matrix-org/synapse/security/advisories/GHSA-jj53-8fmw-f2w2https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2VHDEPCZ22GJFMZCWA2XZAGPOEV72POF/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PXT7ID7DNBRN2TVTETU3SYQHJKEG6PXN/https://github.com/matrix-org/synapse/commit/cb35df940ahttps://github.com/matrix-org/synapse/releases/tag/v1.41.1https://github.com/matrix-org/synapse/security/advisories/GHSA-jj53-8fmw-f2w2https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2VHDEPCZ22GJFMZCWA2XZAGPOEV72POF/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PXT7ID7DNBRN2TVTETU3SYQHJKEG6PXN/
2021-08-31
Published