CVE-2023-43796

Synapse vulnerable to leak of remote user device information

Description

Synapse is an open-source Matrix homeserver Prior to versions 1.95.1 and 1.96.0rc1, cached device information of remote users can be queried from Synapse. This can be used to enumerate the remote users known to a homeserver. System administrators are encouraged to upgrade to Synapse 1.95.1 or 1.96.0rc1 to receive a patch. As a workaround, the `federation_domain_whitelist` can be used to limit federation traffic with a homeserver.

Category

5.3
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.17%
Vendor Advisory github.com
Affected: matrix-org synapse
Published at:
Updated at:

References

Link Tags
https://github.com/matrix-org/synapse/security/advisories/GHSA-mp92-3jfm-3575 vendor advisory
https://github.com/matrix-org/synapse/commit/daec55e1fe120c564240c5386e77941372bf458f patch
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/VH3RNC5ZPQZ4OKPSL4E6BBJSZOQLGDEY/ mailing list
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/2IDEEZMFJBDLTFHQUTZRJJNCOZGQ2ZVS/ mailing list
https://security.gentoo.org/glsa/202401-12

Frequently Asked Questions

What is the severity of CVE-2023-43796?
CVE-2023-43796 has been scored as a medium severity vulnerability.
How to fix CVE-2023-43796?
To fix CVE-2023-43796, 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-2023-43796 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-43796 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-2023-43796?
CVE-2023-43796 affects matrix-org synapse.
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