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CVE-2023-45129

matrix-synapse vulnerable to denial of service due to malicious server ACL events

Published: Oct 10, 2023Updated: Nov 21, 2024 Sources: CVE List NVD GHSA BDUCWE-770
NVD MITRE
4.9CVSSMEDIUM
EPSS Score
1.2%
Top 36.8%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. Prior to version 1.94.0, a malicious server ACL event can impact performance temporarily or permanently leading to a persistent denial of service. Homeservers running on a closed federation (which presumably do not need to use server ACLs) are not affected. Server administrators are advised to upgrade to Synapse 1.94.0 or later. As a workaround, rooms with malicious server ACL events can be purged and blocked using the admin API.

CVSS Vector Breakdown

AV:NAC:LPR:HUI:NS:UC:NI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:HPrivileges Required
High
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
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Weaknesses

CWE-770

Affected Products

synapsematrix-org
On-premWeb App
Communications / messaging-chat
synapsematrix
On-premWeb App
Communications / messaging-chat
fedorafedoraproject
On-premOS
Operating Systems / linux-distro
matrix-synapsePyPIOSS Libraries
openSUSE TumbleweedNovell Inc.
On-premOS
Operating Systems / linux-distro
matrix-orgoss-projectDECommunicationsaka synapse, matrix-js-sdk, matrix appservice irc
matrixoss-projectGBCommunicationsaka synapse, matrix irc bridge, javascript sdk
fedoraprojectoss-projectUSOperating Systemsaka fedora project
pypipackage-ecosystemOSS Libraries
novell inc.commercialUSOperating Systems
and 2 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

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Exploitability

Official Patch Available

MITRE ATT&CK

1 technique
Impact
View detailed technique mapping

References

https://github.com/matrix-org/synapse/security/advisories/GHSA-5chr-wjw5-3gq4
github.com
https://github.com/matrix-org/synapse/pull/16360
github.com
https://matrix-org.github.io/synapse/latest/admin_api/rooms.html#version-2-new-version
matrix-org.github.io
and 15 more references View all →

Timeline

Published
Oct 10, 2023
Last Updated
Nov 21, 2024

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