matrix-synapse vulnerable to denial of service due to malicious server ACL events
CVE-2023-45129

4.9MEDIUM

Key Information:

Vendor

Matrix-org

Status
Synapse
Vendor
CVE Published:
10 October 2023

What is CVE-2023-45129?

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.

Affected Version(s)

synapse < 1.94.0

References

https://github.com/matrix-org/synapse/security/advisories...
x_refsource_CONFIRM
https://github.com/matrix-org/synapse/pull/16360
x_refsource_MISC
https://matrix-org.github.io/synapse/latest/admin_api/roo...
x_refsource_MISC

CVSS V3.1

Score:
4.9
Severity:
MEDIUM
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
High
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.