CVE-2026-33870

HIGH

Netty: HTTP Request Smuggling via Chunked Extension Quoted-String Parsing

Title source: cna

Description

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.

References (4)

[X_Refsource_Misc] https://w4ke.info/2025/06/18/funky-chunks.html

[X_Refsource_Confirm] https://github.com/netty/netty/security/advisories/GHSA-pwqr-wmgm-9rr8

[X_Refsource_Misc] https://w4ke.info/2025/10/29/funky-chunks-2.html

[X_Refsource_Misc] https://www.rfc-editor.org/rfc/rfc9110

Scores

CVSS v3 7.5

EPSS 0.0001

EPSS Percentile 3.1%

Attack Vector NETWORK

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CISA SSVC

Vulnrichment

Exploitation poc

Automatable yes

Technical Impact partial

Details

CWE

CWE-444

Status published

Products (4)

io.netty/netty-codec-http 0 - 4.1.132.FinalMaven

netty/netty < 4.1.132

netty/netty < 4.1.132.Final

netty/netty >= 4.2.0.Alpha1, < 4.2.10.Final

Published Mar 27, 2026

Tracked Since Mar 29, 2026