netty netty-codec-http up to 4.1.133.Final/4.2.13.Final request smuggling

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.3$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, has been found in netty netty-codec-http up to 4.1.133.Final/4.2.13.Final. Affected by this vulnerability is an unknown functionality. Performing a manipulation results in request smuggling. This vulnerability was named CVE-2026-42580. The attack may be initiated remotely. There is no available exploit. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in netty netty-codec-http up to 4.1.133.Final/4.2.13.Final. This affects an unknown functionality. The manipulation with an unknown input leads to a request smuggling vulnerability. CWE is classifying the issue as CWE-444. The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination. This is going to have an impact on integrity, and availability. The summary by CVE is:

Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, Netty's chunk size parser silently overflows int, enabling request smuggling attacks. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.

The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2026-42580 since 04/28/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 321020 (SUSE SLED15 / SLES15 Security Update : netty, netty-tcnative (SUSE-SU-2026:2308-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.1.133.Final or 4.2.13.Final eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (321020). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.5
VulDB Meta Temp Score: 6.3

VulDB Base Score: 6.5
VulDB Temp Score: 6.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.5
CNA Vector (GitHub_M): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Request smuggling
CWE: CWE-444
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 321020
Nessus Name: SUSE SLED15 / SLES15 Security Update : netty, netty-tcnative (SUSE-SU-2026:2308-1)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: netty-codec-http 4.1.133.Final/4.2.13.Final

Timelineinfo

04/28/2026 CVE reserved
05/13/2026 +15 days Advisory disclosed
05/13/2026 +0 days VulDB entry created
06/15/2026 +33 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-42580 (🔒)
GCVE (CVE): GCVE-0-2026-42580
GCVE (VulDB): GCVE-100-363693

Entryinfo

Created: 05/13/2026 20:53
Updated: 06/15/2026 04:35
Changes: 05/13/2026 20:53 (62), 06/15/2026 04:35 (2)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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