CVE-2023-43796

unknown
Published 2023-10-31 · Modified 2023-11-08
CVSS v3
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
CVSS v2
VIR risk

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.

Predictions

Exploit likelihood
30%
Patch ETA

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2023-43796

OS impact

OSVersionStatusFixed in
debian debianforkyfixed1.95.1-1
debian debiansidfixed1.95.1-1

Package impact

EcosystemPackageVulnerableFixed
python PyPImatrix-synapse<1.95.11.95.1
python PyPImatrix-synapse<daec55e1fe120c564240c5386e77941372bf458f||<1.95.1daec55e1fe120c564240c5386e77941372bf458f

References

Verify integrity in audit chain (admin only). AS-IS.