CVE-2021-33175: Emqx Emq X Broker

High severity, CVSS 7.5. EPSS: 1.1% chance of exploitation in the next 30 days.

EMQ X Broker versions prior to 4.2.8 are vulnerable to a denial of service attack as a result of excessive memory consumption due to the handling of untrusted inputs. These inputs cause the message broker to consume large amounts of memory, resulting in the application being terminated by the operating system.

Affected products

• Emqx Emq X Broker: before 4.2.8 (fixed in 4.2.8)

Published 2021-06-08. Last modified 2026-06-17.