CVE-2026-8741

A vulnerability has been found in EMQX up to 6.2.0. This affects an unknown function of the file apps/emqx/src/emqx_persistent_session_ds.erl of the component QoS 2 PUBLISH Packet Handler. Such manipulation leads to race condition. The attack may be performed from remote. A high complexity level is associated with this attack. The exploitability is reported as difficult. The exploit has been disclosed to the public and may be used. The vendor was contacted early about this disclosure.

CVSS v3 3.1 LOW
CVSS v2.0 2.1 LOW

3.1^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.6 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

2.1^/10

CVSS v2.0 : LOW

Vector : AV:N/AC:H/Au:S/C:N/I:N/A:P

Exploitability : 3.9 / Impact : 2.9

Access Vector NETWORK

Access Complexity HIGH

Authentication SINGLE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact PARTIAL

References

Link	Resource
https://github.com/Pathfind-tama/Report_EMQX_MQTT	Third Party Advisory
https://github.com/Pathfind-tama/Report_EMQX_MQTT/blob/main/MQTT%20QoS%202%20Message%20Duplication%20in%20Persistent%20Sessions.md	Exploit Mitigation Third Party Advisory
https://vuldb.com/submit/809931	Third Party Advisory VDB Entry
https://vuldb.com/vuln/364329	Third Party Advisory VDB Entry
https://vuldb.com/vuln/364329/cti	Permissions Required VDB Entry

Configurations

Configuration 1 (hide)

cpe:2.3:a:emqx:emqx:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-05-17 09:16

Updated : 2026-06-17 11:04

NVD link : CVE-2026-8741

Mitre link : CVE-2026-8741

CVE.ORG link : CVE-2026-8741

JSON object : View

Products Affected

emqx

emqx

CWE

CWE-362

Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

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