CVE-2022-39374

Synapse Denial of service due to incorrect application of event authorization rules during state resolution

Description

Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. If Synapse and a malicious homeserver are both joined to the same room, the malicious homeserver can trick Synapse into accepting previously rejected events into its view of the current state of that room. This can be exploited in a way that causes all further messages and state changes sent in that room from the vulnerable homeserver to be rejected. This issue has been patched in version 1.68.0

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 3.0 •
EPSS 0.16%
Vendor Advisory github.com
Affected: matrix-org synapse
Published at:
Updated at:

References

Link Tags
https://github.com/matrix-org/synapse/security/advisories/GHSA-p9qp-c452-f9r7 mitigation vendor advisory
https://github.com/matrix-org/synapse/pull/13723 patch issue tracking
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UJIJRP5ZH6B3KGFLHCAKR2IX2Y4Z25QD/

Frequently Asked Questions

What is the severity of CVE-2022-39374?
CVE-2022-39374 has been scored as a medium severity vulnerability.
How to fix CVE-2022-39374?
To fix CVE-2022-39374, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2022-39374 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2022-39374 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2022-39374?
CVE-2022-39374 affects matrix-org synapse.
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