Resource exhaustion in Netty - CVE-2026-44248
Published: May 5, 2026
Vulnerability identifier: #VU130204
CSH Severity: Medium
CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-44248
CWE-ID: CWE-400
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
Netty
Netty
Software vendor:
Netty project
Netty project
Description
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to uncontrolled resource consumption in MqttDecoder when parsing MQTT 5 header Properties sections. A remote attacker can send a specially crafted MQTT message with an enormous Properties section to cause a denial of service.
The issue can lead to high CPU and memory usage because the Properties section is parsed and buffered before message size limits are applied, and repeated re-parsing occurs due to ReplayingDecoder behavior.
Remediation
Install security update from vendor's website.