CVE-2022-41952
Publication date 22 November 2022
Last updated 24 July 2024
Ubuntu priority
Cvss 3 Severity Score
Synapse before 1.52.0 with URL preview functionality enabled will attempt to generate URL previews for media stream URLs without properly limiting connection time. Connections will only be terminated after `max_spider_size` (default: 10M) bytes have been downloaded, which can in some cases lead to long-lived connections towards the streaming media server (for instance, Icecast). This can cause excessive traffic and connections toward such servers if their stream URL is, for example, posted to a large room with many Synapse instances with URL preview enabled. Version 1.52.0 implements a timeout mechanism which will terminate URL preview connections after 30 seconds. Since generating URL previews for media streams is not supported and always fails, 1.53.0 additionally implements an allow list for content types for which Synapse will even attempt to generate a URL preview. Upgrade to 1.53.0 to fully resolve the issue. As a workaround, turn off URL preview functionality by setting `url_preview_enabled: false` in the Synapse configuration file.
Status
Package | Ubuntu Release | Status |
---|---|---|
matrix-synapse | 24.10 oracular |
Not affected
|
24.04 LTS noble |
Not affected
|
|
22.04 LTS jammy |
Not affected
|
|
20.04 LTS focal |
Needs evaluation
|
|
18.04 LTS bionic |
Needs evaluation
|
|
16.04 LTS xenial | Ignored end of standard support | |
14.04 LTS trusty | Ignored end of standard support |
Severity score breakdown
Parameter | Value |
---|---|
Base score | 5.3 · Medium |
Attack vector | Network |
Attack complexity | Low |
Privileges required | None |
User interaction | None |
Scope | Unchanged |
Confidentiality | None |
Integrity impact | None |
Availability impact | Low |
Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
References
Other references
- https://github.com/matrix-org/synapse/security/advisories/GHSA-4822-jvwx-w47h
- https://github.com/matrix-org/synapse/pull/11784
- https://github.com/matrix-org/synapse/pull/11936
- https://github.com/matrix-org/synapse/releases/tag/v1.53.0
- https://github.com/matrix-org/synapse/releases/tag/v1.52.0
- https://www.cve.org/CVERecord?id=CVE-2022-41952