CVE-2018-12543 Denial of service in Eclipse Mosquitto

High 7.5 Published 15 Nov 2018 Updated 5 Aug 2024

An attacker can crash the Eclipse Mosquitto MQTT broker by publishing a message with a specific topic starting with a dollar sign.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2018-12543?

CVE-2018-12543 is a high-severity denial of service vulnerability in The Eclipse Foundation Eclipse Mosquitto, published on 15 Nov 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

In Eclipse Mosquitto versions 1.5 to 1.5.2 inclusive, if a message is published to Mosquitto that has a topic starting with $, but that is not $SYS, e.g. $test/test, then an assert is triggered that should otherwise not be reachable and Mosquitto will exit.

Weakness: CWE-20, CWE-617

Which versions are affected by CVE-2018-12543?

It affects 1 product.

Products include Eclipse Mosquitto.

How do I fix CVE-2018-12543?

Upgrade to a fixed version.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2018-12543 being exploited?

There is no known exploitation of CVE-2018-12543 in the wild and no public exploit code.

Sources

Also known as ALPINE-CVE-2018-12543, GHSA-4g6q-vx9q-q84r.