CVE-2022-31052

 

Published at: - 28-06-2022 07:15

Last modified: - 09-07-2022 02:15

Total changes: - 4

Description

Synapse is an open source home server implementation for the Matrix chat network. In versions prior to 1.61.1 URL previews of some web pages can exhaust the available stack space for the Synapse process due to unbounded recursion. This is sometimes recoverable and leads to an error for the request causing the problem, but in other cases the Synapse process may crash altogether. It is possible to exploit this maliciously, either by malicious users on the homeserver, or by remote users sending URLs that a local user's client may automatically request a URL preview for. Remote users are not able to exploit this directly, because the URL preview endpoint is authenticated. Deployments with `url_preview_enabled: false` set in configuration are not affected. Deployments with `url_preview_enabled: true` set in configuration **are** affected. Deployments with no configuration value set for `url_preview_enabled` are not affected, because the default is `false`. Administrators of homeservers with URL previews enabled are advised to upgrade to v1.61.1 or higher. Users unable to upgrade should set `url_preview_enabled` to false.

Common Vulnerability Scoring System (CVSS)

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

 

Verification logic

 

Reference

• https://github.com/matrix-org/synapse/security/advisories/GHSA-22p3-qrh9-cx32
• https://spec.matrix.org/v1.2/client-server-api/#get_matrixmediav3preview_url
• https://github.com/matrix-org/synapse/commit/fa1308061802ac7b7d20e954ba7372c5ac292333
• FEDORA-2022-1a2312e4d6-Mailing List, Third Party Advisory
• FEDORA-2022-45bf6d4b88-Mailing List, Third Party Advisory

 

Keywords

NVD

 

CVE-2022-31052

 

CVE

 

Common vulnerabilities & exposures

 

CVSS

 

Common vulnerability scoring system

 

Security

 

Vulnerabilities

 

Exposures