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.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - 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.
    (CVE-2022-31052)

Note that Nessus relies on the presence of the package as reported by the vendor.

The version of FreeBSD installed on the remote host is prior to tested version. It is, therefore, affected by a vulnerability as referenced in the 07c0d782-f758-11ec-acaa-901b0e9408dc advisory.

  - 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.
    (CVE-2022-31052)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Severity
256598	Linux Distros Unpatched Vulnerability : CVE-2022-31052	Nessus	Misc.	medium
162586	FreeBSD : py-matrix-synapse -- unbounded recursion in urlpreview (07c0d782-f758-11ec-acaa-901b0e9408dc)	Nessus	FreeBSD Local Security Checks	medium

Detections

Analytics

CVE-2022-31052

high

Tenable Plugins

medium

medium