CVE-2026-33870

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

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

netty

CVSS v3.1 CNA

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

EPSS

0.70% chance of exploitation in the next 30 days, 52nd percentile

Published

2026-03-27

Updated

2026-09-15

Proof-of-concept exploits (1)

• advisories/GHSA-pwqr-wmgm-9rr8

Security advisories

• netty/netty/security/advisories/GHSA-pwqr-wmgm-9rr8

References

• CVE Record
• NVD entry