CVE-2022-31052

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 users 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.

Risk Information

Base Score

6.5

MODERATE

Vector

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

EPSS Score

Exploitation Probability

0.742

Associated Vulnerability

Vulnerability	OS Platform
Vulnerabilities CVE-2022-31052 are fixed in Python-matrix-synapse 1.61.1	Windows
Vulnerabilities CVE-2022-31052 are fixed in Python-matrix-synapse for linux 1.61.1	Linux

Patch Details

No records found

References

https://nvd.nist.gov/vuln/detail/CVE-2023-1234
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-1234