CVE-2026-33870
Netty: HTTP Request Smuggling via Chunked Extension Quoted-String Parsing
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.
INFO
Published Date :
March 27, 2026, 8:16 p.m.
Last Modified :
March 30, 2026, 8:12 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Update Netty to version 4.1.132.Final or later.
- Update Netty to version 4.2.10.Final or later.
Public PoC/Exploit Available at Github
CVE-2026-33870 has a 3 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-33870.
| URL | Resource |
|---|---|
| https://github.com/netty/netty/security/advisories/GHSA-pwqr-wmgm-9rr8 | Exploit Mitigation Vendor Advisory |
| https://w4ke.info/2025/06/18/funky-chunks.html | Technical Description |
| https://w4ke.info/2025/10/29/funky-chunks-2.html | Technical Description |
| https://www.rfc-editor.org/rfc/rfc9110 | Technical Description |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-33870 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-33870
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
None
VEX (Vulnerability Exploitability eXchange) repository for Liquibase products. Provides machine-readable vulnerability assessments for automated scanner integration.
sbom security supply-chain-security vex
Kafka sink for Kusto
kafka-connector azure-data-explorer kusto
Java Shell Dockerfile
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-33870 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-33870 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Mar. 30, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:* versions up to (excluding) 4.1.132 *cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:* versions from (including) 4.2.0 up to (excluding) 4.2.10 Added Reference Type GitHub, Inc.: https://github.com/netty/netty/security/advisories/GHSA-pwqr-wmgm-9rr8 Types: Exploit, Mitigation, Vendor Advisory Added Reference Type GitHub, Inc.: https://w4ke.info/2025/06/18/funky-chunks.html Types: Technical Description Added Reference Type GitHub, Inc.: https://w4ke.info/2025/10/29/funky-chunks-2.html Types: Technical Description Added Reference Type GitHub, Inc.: https://www.rfc-editor.org/rfc/rfc9110 Types: Technical Description -
New CVE Received by [email protected]
Mar. 27, 2026
Action Type Old Value New Value Added 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. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N Added CWE CWE-444 Added Reference https://github.com/netty/netty/security/advisories/GHSA-pwqr-wmgm-9rr8 Added Reference https://w4ke.info/2025/06/18/funky-chunks.html Added Reference https://w4ke.info/2025/10/29/funky-chunks-2.html Added Reference https://www.rfc-editor.org/rfc/rfc9110