Vulnerability 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.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Matrix | Synapse | < 1.61.1 |
| Fedoraproject | Fedora | 35 |
Related Weaknesses (CWE)
References
- https://github.com/matrix-org/synapse/commit/fa1308061802ac7b7d20e954ba7372c5ac2PatchThird Party Advisory
- https://github.com/matrix-org/synapse/security/advisories/GHSA-22p3-qrh9-cx32Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://spec.matrix.org/v1.2/client-server-api/#get_matrixmediav3preview_urlVendor Advisory
- https://github.com/matrix-org/synapse/commit/fa1308061802ac7b7d20e954ba7372c5ac2PatchThird Party Advisory
- https://github.com/matrix-org/synapse/security/advisories/GHSA-22p3-qrh9-cx32Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://spec.matrix.org/v1.2/client-server-api/#get_matrixmediav3preview_urlVendor Advisory
FAQ
What is CVE-2022-31052?
CVE-2022-31052 is a vulnerability with a CVSS score of 6.5 (MEDIUM). 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 proce...
How severe is CVE-2022-31052?
CVE-2022-31052 has been rated MEDIUM with a CVSS base score of 6.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2022-31052?
Check the references section above for vendor advisories and patch information. Affected products include: Matrix Synapse, Fedoraproject Fedora.