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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
NVD MITRE
5.3CVSSMEDIUM
EPSS Score
0.9%
Top 45.2%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

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.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:LI:NA:N
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-200NVD-CWE-noinfo

Affected Products

synapsematrix
On-premWeb App
Communications / messaging-chat
fedorafedoraproject
On-premOS
Operating Systems / linux-distro
synapsematrix-org
On-premWeb App
Communications / messaging-chat
matrix-synapsePyPIOSS Libraries
matrixoss-projectGBCommunicationsaka synapse, matrix irc bridge, javascript sdk
fedoraprojectoss-projectUSOperating Systemsaka fedora project
matrix-orgoss-projectDECommunicationsaka synapse, matrix-js-sdk, matrix appservice irc
pypipackage-ecosystemOSS Libraries

Attack Graph

Products CVE Techniques Tactics

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Exploitability

Official Patch Available

MITRE ATT&CK

1 technique
Collection
View detailed technique mapping

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 →

Timeline

Published
Oct 31, 2023
Last Updated
Feb 13, 2025

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