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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
5.3MEDIUM
NVD MITRE
EPSS Score
0.9%
Top 43.8%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

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

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

matrix
oss-project·GBaka synapse, matrix irc bridge, javascript sdk
synapseOn-premWeb App
Communications / messaging-chat
fedoraproject
oss-project·USaka fedora project
fedoraOn-premOS
Operating Systems / linux-distro
matrix-org
oss-project·DEaka matrix appservice irc, synapse, 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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