Description
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.
Affected products
netty: netty
References10
- github.com/netty/netty/security/advisories/GHSA-45q3-82m4-75jr ExploitMitigationVendor Advisory
- github.com/netty/netty/security/advisories/GHSA-45q3-82m4-75jr ExploitMitigationVendor Advisory
- access.redhat.com/errata/RHSA-2026:23808
- access.redhat.com/errata/RHSA-2026:24502
- access.redhat.com/errata/RHSA-2026:25123
- access.redhat.com/errata/RHSA-2026:28010
- access.redhat.com/errata/RHSA-2026:36820
- access.redhat.com/errata/RHSA-2026:37390
- access.redhat.com/errata/RHSA-2026:42644
- access.redhat.com/errata/RHSA-2026:49700
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - CVSS 4.0
-
2.9
LOW
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 1% percentile: 65 · as of 14 November 2026
- CWE
- CWE-113CWE-93
Could this be exploited in your environment?
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