CVE-2026-33870

high

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

https://www.rfc-editor.org/rfc/rfc9110

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

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

https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33870.json

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

https://bugzilla.redhat.com/show_bug.cgi?id=2452453

https://access.redhat.com/security/cve/CVE-2026-33870

https://access.redhat.com/errata/RHSA-2026:8509

https://access.redhat.com/errata/RHSA-2026:8159

https://access.redhat.com/errata/RHSA-2026:7380

https://access.redhat.com/errata/RHSA-2026:7109

https://access.redhat.com/errata/RHSA-2026:65126

https://access.redhat.com/errata/RHSA-2026:34608

https://access.redhat.com/errata/RHSA-2026:22619

https://access.redhat.com/errata/RHSA-2026:18059

https://access.redhat.com/errata/RHSA-2026:18055

https://access.redhat.com/errata/RHSA-2026:18054

https://access.redhat.com/errata/RHSA-2026:17789

https://access.redhat.com/errata/RHSA-2026:17668

https://access.redhat.com/errata/RHSA-2026:14276

https://access.redhat.com/errata/RHSA-2026:14272

https://access.redhat.com/errata/RHSA-2026:13571

https://access.redhat.com/errata/RHSA-2026:10184

https://access.redhat.com/errata/RHSA-2026:10175

Details

Source: Mitre, NVD

Published: 2026-03-27

Updated: 2026-09-14

Risk Information

CVSS v2

Base Score: 7.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:C/A:N

Severity: High

CVSS v3

Base Score: 7.5

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

Severity: High

EPSS

EPSS: 0.00029