VULNERABILITY INTELLIGENCE

CVE-2026-76816

CVSS score3.5 LOW
EPSS probability0.17%
CISA KEVNot currently listed
Published2026-08-24
Last modified2026-10-12
CVSS vectorCVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

Description

Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.137.Final and 4.2.17.Final, MqttEncoder does not validate client identifiers, will topics, usernames, and PUBLISH topic names before encoding, allowing prohibited null bytes in MQTT UTF-8 string fields and potentially causing routing, access-control, or identity mismatches in downstream brokers. The vulnerability is exploitable when an application uses Netty's MQTT encoder to construct messages from user-controlled input. This issue is fixed in versions 4.1.137.Final and 4.2.17.Final.

Weakness classification

  • security-advisories@github.com: CWE-20

Primary references