CVE-2022-31152

Name: CVE-2022-31152
Creator: NVD / NIST
Published: 2022-09-02T20:15:08.37+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 0.90%

Last modified Jun 17, 2026

CVE-2022-31152 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. The Matrix specification specifies a list of [event authorization rules](https://spec.matrix.org/v1.2/rooms/v9/#authorization-rules) which must be checked when determining if an event should be accepted into a room. EPSS estimates a 0.90% chance of exploitation in the next 30 days.

Description

Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. The Matrix specification specifies a list of [event authorization rules](https://spec.matrix.org/v1.2/rooms/v9/#authorization-rules) which must be checked when determining if an event should be accepted into a room. In versions of Synapse up to and including version 1.61.0, some of these rules are not correctly applied. An attacker could craft events which would be accepted by Synapse but not a spec-conformant server, potentially causing divergence in the room state between servers. Administrators of homeservers with federation enabled are advised to upgrade to version 1.62.0 or higher. Federation can be disabled by setting [`federation_domain_whitelist`](https://matrix-org.github.io/synapse/latest/usage/configuration/config_documentation.html#federation_domain_whitelist) to an empty list (`[]`) as a workaround.

Metrics

CVSS 3.1

7.5/10

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

EPSS Probability

0.90%

55.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Matrix	Synapse	< 1.62.0

References

https://github.com/matrix-org/synapse/pull/13087Issue Tracking, Patch, Third Party Advisory
https://github.com/matrix-org/synapse/pull/13088Issue Tracking, Patch, Third Party Advisory
https://github.com/matrix-org/synapse/releases/tag/v1.62.0Release Notes, Third Party Advisory
https://github.com/matrix-org/synapse/security/advisories/GHSA-jhjh-776m-4765Issue Tracking, Mitigation, Third Party Advisory
https://github.com/matrix-org/synapse/pull/13087Issue Tracking, Patch, Third Party Advisory
https://github.com/matrix-org/synapse/pull/13088Issue Tracking, Patch, Third Party Advisory
https://github.com/matrix-org/synapse/releases/tag/v1.62.0Release Notes, Third Party Advisory
https://github.com/matrix-org/synapse/security/advisories/GHSA-jhjh-776m-4765Issue Tracking, Mitigation, Third Party Advisory

Timeline

Published: Sep 2, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2022-31152?

How severe is CVE-2022-31152?

CVE-2022-31152 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 0.90% probability of exploitation in the next 30 days.

How do I fix CVE-2022-31152?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2022-31152?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST