CVE-2023-45129mediumCWE-770

CVE-2023-45129: medium-severity vulnerability in matrix-org synapse

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

Published · Updated

Follow this CVE+ Monitor synapse+ Monitor matrix-synapse

E-mail alert when it lands in KEV, gets a public PoC or its score goes up.

13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 4.9epss 1.4%
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:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
Affected products
matrix-org · synapse
Related CVEs — matrix-org synapse

In the same product, most dangerous first.

CVE-2020-26257MEDIUMDenial of service attack via incorrect parameters to federation APIsEPSS 2.4%CVE-2021-21274MEDIUMDenial of service attack via .well-known lookupsEPSS 2.2%CVE-2021-21273LOWOpen redirects on some federation and push requestsEPSS 1.8%CVE-2022-31052MEDIUMURL previews can crash Synapse media repositories or Synapse monolithsEPSS 1.7%CVE-2021-29471LOWDenial of service in Matrix SynapseEPSS 1.6%CVE-2021-21393MEDIUMDenial of service (via resource exhaustion) due to improper input validation on groups/communities endpointsEPSS 1.6%