CVE-2026-42578

Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, Netty's HttpProxyHandler constructs HTTP CONNECT requests with header validation explicitly disabled. The newInitialMessage() method creates headers using DefaultHttpHeadersFactory.headersFactory().withValidation(false), then adds user-provided outboundHeaders without any CRLF validation. This allows an attacker who can influence the outbound headers to inject arbitrary HTTP headers into the CONNECT request sent to the proxy server. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.
Configurations

Configuration 1 (hide)

OR cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*
cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*

History

21 Jul 2026, 12:18

Type Values Removed Values Added
References
  • () https://access.redhat.com/errata/RHSA-2026:42644 -

10 Jul 2026, 12:16

Type Values Removed Values Added
References
  • () https://access.redhat.com/errata/RHSA-2026:37390 -

09 Jul 2026, 13:17

Type Values Removed Values Added
References
  • () https://access.redhat.com/errata/RHSA-2026:36820 -

30 Jun 2026, 03:19

Type Values Removed Values Added
CWE CWE-93
References
  • () https://access.redhat.com/errata/RHSA-2026:23808 -
  • () https://access.redhat.com/errata/RHSA-2026:24502 -
  • () https://access.redhat.com/errata/RHSA-2026:25123 -
  • () https://access.redhat.com/errata/RHSA-2026:28010 -
  • () https://access.redhat.com/security/cve/CVE-2026-42578 -
  • () https://bugzilla.redhat.com/show_bug.cgi?id=2477226 -
  • () https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42578.json -

18 May 2026, 12:54

Type Values Removed Values Added
References () https://github.com/netty/netty/security/advisories/GHSA-45q3-82m4-75jr - () https://github.com/netty/netty/security/advisories/GHSA-45q3-82m4-75jr - Exploit, Mitigation, Vendor Advisory
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 7.5
First Time Netty netty
Netty
CPE cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*

13 May 2026, 19:17

Type Values Removed Values Added
New CVE

Information

Published : 2026-05-13 19:17

Updated : 2026-07-21 12:18


NVD link : CVE-2026-42578

Mitre link : CVE-2026-42578

CVE.ORG link : CVE-2026-42578


JSON object : View

Products Affected

netty

  • netty
CWE
CWE-113

Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')

CWE-93

Improper Neutralization of CRLF Sequences ('CRLF Injection')