Mqtt
CVE-2020-13849
HIGH
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A06:2025 - Insecure Design
ASVS 5.0
V2 - Validation and Business Logic Resource consumption limits
MITRE ATT&CK
1 technique across 1 tactic: Impact The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 7.5 (HIGH). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. |
| Exploit ScenarioDerived | A remote attacker could cause denial of service by exhausting system resources by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability. |
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Alert meAnalysisAI
The MQTT protocol 3.1.1 requires a server to set a timeout value of 1.5 times the Keep-Alive value specified by a client, which allows remote attackers to cause a denial of service (loss of the. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Implement rate limiting, set resource quotas, validate input sizes, use timeouts.
Affects your stack
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Technical ContextAI · show details
This vulnerability is classified as Uncontrolled Resource Consumption (CWE-400), which allows attackers to cause denial of service by exhausting system resources. The MQTT protocol 3.1.1 requires a server to set a timeout value of 1.5 times the Keep-Alive value specified by a client, which allows remote attackers to cause a denial of service (loss of the ability to establish new connections), as demonstrated by SlowITe. Affected products include: Mqtt.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
The MQTT protocol 3.1.1 requires a server to set a timeout value of 1.5 times the Keep-Alive value specified by a client, which allows remote attackers to cause a denial of service (loss of the ability to establish new connections), as demonstrated by SlowITe.
Threat Intelligence Overview
NVD
CVE.org
EPSS
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
Affected Products (CPE)NVD
Moquette MQTT brokers running versions prior to 0.18.1 fail to enforce topic write ACLs on Last Will and Testament messa
An out-of-bounds write in the MQTT client module of the lwIP TCP/IP stack lets an adversary who controls or impersonates
Improper TLS hostname validation in the MQTT client layer of AWS IoT Device SDK for Python (AWSIoTPythonSDK) 1.5.3 throu
Remote unauthenticated clients can crash a Moquette MQTT broker running 0.18.0 or earlier by publishing or subscribing w
Hardcoded MQTT credentials shipped inside Bransys ELD grant unauthenticated read access to real-time telemetry for every
Malformed MQTT PUBLISH frames leak packet buffers in the Eclipse ThreadX NetX Duo MQTT client, letting a peer that can d
Remote denial of service in the Aedes MQTT broker through version 1.1.0 lets any client able to open an MQTT session cra
An out-of-bounds read in Eclipse ThreadX NetX Duo's MQTT-over-WebSocket transport (the setter path) lets a malicious or
Loopback source-address restriction bypass in RabbitMQ's native MQTT and MQTT-over-WebSocket listeners (all releases fro
Denial of service in RabbitMQ's MQTT plugin lets an authenticated publisher using MQTT 5 force a single victim subscribe
Authorization bypass in RabbitMQ's MQTT topic permission handling allows a low-privileged authenticated user to broaden
Authenticated users of FlashMQ MQTT brokers running versions prior to 1.23.2 can cause a gradual memory leak by creating
GitHub PoC
Exploit-DB