CVE-2022-39374 - CVE House
Back to Database
Status published Medium CVE-2022-39374

Synapse Denial of service due to incorrect application of event authorization rules during state resolution

Vulnerability Description

Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. If Synapse and a malicious homeserver are both joined to the same room, the malicious homeserver can trick Synapse into accepting previously rejected events into its view of the current state of that room. This can be exploited in a way that causes all further messages and state changes sent in that room from the vulnerable homeserver to be rejected. This issue has been patched in version 1.68.0

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

THREAT MONITOR

Am I Vulnerable?

Launch our assessment wizard to check if your infrastructure is exposed to • CVE-2022-39374

Credits & Attribution

No credits recorded in the NVD database.

References

More from matrix-org

View All →
CVE-2025-66622
matrix-sdk-base is vulnerable to DoS via custom m.room.join_rules event values
Low 1.3
CVE-2025-59160
matrix-js-sdk has insufficient validation when considering a room to be upgraded by another
Low 2.7
CVE-2025-59047
matrix-sdk-base has panic in the `RoomMember::normalized_power_level()` method
Low 2.7
CVE-2025-53549
Matrix Rust SDK allows SQL injection in the EventCache implementation
Medium 5.2
CVE-2025-48937
matrix-sdk-crypto vulnerable to sender of encrypted events being spoofed by homeserver administrator
Medium 4.9

Affected Vendor

Affected Software

synapse
Vulnerable Versions:
>= 1.62.0, < 1.68.0

Timeline

Official Publish: May 26th, 2023
Last Modified: February 13th, 2025
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weaknesses (CWE)

CWE-400

MITRE ATT&CK TTPs

T1499 Endpoint Denial of Service
Impact
T1498 Network Denial of Service
Impact