CVE-2026-93574
Published:September 18, 2026
Updated:October 09, 2026
A flaw was found in Netty's "netty-codec-http" component. A remote attacker could exploit this vulnerability by sending a specially crafted HTTP/1.1 chunk-size token that includes post-digit whitespace. This incorrect parsing of the chunk size can lead to HTTP request smuggling. This allows an attacker to bypass security controls or access unauthorized resources in proxy/backend deployments.
Affected Packages
https://github.com/netty/netty.git (GITHUB):
Affected version(s) >=netty-4.1.90.Final <netty-4.1.138.FinalFix Suggestion:
Update to version netty-4.1.138.Finalhttps://github.com/netty/netty.git (GITHUB):
Affected version(s) >=netty-4.2.0.Alpha1 <netty-4.2.18.FinalFix Suggestion:
Update to version netty-4.2.18.Finalio.netty:netty-codec-http (JAVA):
Affected version(s) >=4.2.0.Alpha1 <4.2.18.FinalFix Suggestion:
Update to version 4.2.18.Finalio.netty:netty-codec-http (JAVA):
Affected version(s) >=4.1.90.Final <4.1.138.FinalFix Suggestion:
Update to version 4.1.138.Finalio.netty:netty-all (JAVA):
Affected version(s) >=4.1.0.Beta1 <4.1.138.FinalFix Suggestion:
Update to version 4.1.138.FinalRelated Resources (5)
Do you need more information?
Contact UsCVSS v4
Base Score:
6.9
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
LOW
Vulnerable System Availability
LOW
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
6.5
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
LOW
Weakness Type (CWE)
Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
EPSS
Base Score:
1.35