CVE-2023-3592Network attack vector

Unauthenticated broker denial of service via Will-property leak

Published Oct 2, 2023 · Updated Feb 13, 2025

Memory leak in Eclipse Mosquitto before 2.0.16 allows remote attackers to exhaust broker memory via malformed MQTT v5 CONNECT packets. property__process_will returns on an invalid Will-property type without attaching the parsed property list to the message, leaving that allocation unreleased. No authentication or user interaction is required; repeated packets consume memory until the broker becomes unresponsive.

CVSS severity7.5
High
EPSS probability0.79%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Memory leak in Eclipse Mosquitto before 2.0.16 allows remote attackers to exhaust broker memory via malformed MQTT v5 CONNECT packets. property__process_will returns on an invalid Will-property type without attaching the parsed property list to the message, leaving that allocation unreleased. No authentication or user interaction is required; repeated packets consume memory until the broker becomes unresponsive.

The record

CVE
CVE-2023-3592
Published
Oct 2, 2023
Updated
Feb 13, 2025
Vendor
The Eclipse Foundation
Product
Eclipse Mosquitto
Classifications
CWE-401, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 2, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 13, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <2.0.16

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Eclipse Foundation · Eclipse Mosquittoversion=0 <2.0.16

Published CVSS scores

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
5.8UbuntuCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-401Missing Release of Memory after Effective Lifetime
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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