HOMEVULNERABILITIESCVE-2022-39374
MEDIUM

CVE-2022-39374

CWE-400Published: May 26, 2023· Updated: Jun 17, 2026

6.5
CVSS v3.1

Official 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

NVD Source

Technical Analysis

CVE-2022-39374 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

A successful exploit results in availability disruption (denial of service), with a CVSS base score of 6.5.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.Low
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityNone
IntegrityNone
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected Vendors & Products

matrix1 product(s)
synapse
Source: NVD CPE · 1 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
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Official Patches & Advisories

PATCHhttps://github.com/matrix-org/synapse/pull/13723
PATCHhttps://github.com/matrix-org/synapse/pull/13723
ADVISORYhttps://github.com/matrix-org/synapse/security/advisories/GHSA-p9qp-c452-f9r7
ADVISORYhttps://github.com/matrix-org/synapse/security/advisories/GHSA-p9qp-c452-f9r7

All References (6)

→
https://github.com/matrix-org/synapse/pull/13723Issue Tracking · Patch
→
https://github.com/matrix-org/synapse/security/advisories/GHSA-p9qp-c452-f9r7Mitigation · Vendor Advisory
→
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UJIJRP5ZH6B3KGFLHCAKR2IX2Y4Z25QD/
→
https://github.com/matrix-org/synapse/pull/13723Issue Tracking · Patch
→
https://github.com/matrix-org/synapse/security/advisories/GHSA-p9qp-c452-f9r7Mitigation · Vendor Advisory
→
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UJIJRP5ZH6B3KGFLHCAKR2IX2Y4Z25QD/

Quick Facts

CVE IDCVE-2022-39374
CVSS Score6.5 / 10
SeverityMEDIUM
WeaknessCWE-400
CISA KEVNo
Affected1 vendor(s)
PublishedMay 26, 2023

Related CVEs (CWE-400)

CVE-2018-16489
9.8
CVE-2018-16486
9.8
CVE-2025-43193
9.8
CVE-2017-9119
9.8
CVE-2017-1000378
9.8
CVE-2018-16491
9.8

Recommended Actions

  • →Apply vendor patches immediately
  • →Monitor CVE-2022-39374 in threat intel feeds
  • →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWatch. CVE data is provided under the NVD usage policy.
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