CVE-2023-43796

Synapse vulnerable to leak of remote user device information

Published: Oct 31, 2023Updated: Feb 13, 2025 Sources: CVE List NVD GHSACWE-200

5.3MEDIUM

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:LConfidentiality

Low

I:NIntegrity

None

A:NAvailability

None

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Weaknesses

CWE-200 NVD-CWE-noinfo

Affected Products

matrix

oss-project·GBaka javascript sdk, synapse, matrix irc bridge

synapseOn-premWeb App

Communications / messaging-chat

fedoraproject

oss-project·USaka fedora project

fedoraOn-premOS

Operating Systems / linux-distro

matrix-org

oss-project·DEaka synapse, matrix appservice irc, matrix-js-sdk

synapseOn-premWeb App

Communications / messaging-chat

PyPI

package-ecosystem

matrix-synapse

OSS Libraries

Exploitability

Official Patch Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Collection

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References

https://github.com/matrix-org/synapse/commit/daec55e1fe120c564240c5386e77941372bf458f

github.com

https://github.com/matrix-org/synapse/security/advisories/GHSA-mp92-3jfm-3575

github.com

https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/2IDEEZMFJBDLTFHQUTZRJJNCOZGQ2ZVS/

lists.fedoraproject.org

and 7 more references View all →

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