CVE-2026-33870: Netty

High severity, CVSS 7.5. EPSS: 0.7% chance of exploitation in the next 30 days.

Netty is an asynchronous, event-driven network application framework. In versions prior to 4.1.132.Final and 4.2.10.Final, Netty incorrectly parses quoted strings in HTTP/1.1 chunked transfer encoding extension values, enabling request smuggling attacks. Versions 4.1.132.Final and 4.2.10.Final fix the issue.

Affected products

• Netty Netty: before 4.1.132 (fixed in 4.1.132); from 4.2.0, before 4.2.10 (fixed in 4.2.10)

Published 2026-03-27. Last modified 2026-09-14.