PT-2026-38371 · Netty+2 · Netty+2
Published
2026-05-07
·
Updated
2026-06-09
·
CVE-2026-42578
CVSS v3.1
7.5
High
| Vector | AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N |
Name of the Vulnerable Software and Affected Versions
Netty versions prior to 4.1.133.Final
Netty versions prior to 4.2.13.Final
Description
Netty's
HttpProxyHandler constructs HTTP CONNECT requests with header validation explicitly disabled. The newInitialMessage() function creates headers using DefaultHttpHeadersFactory.headersFactory().withValidation(false), then adds user-provided outboundHeaders without any CRLF (Carriage Return Line Feed) validation. CRLF injection is a technique where an attacker inserts special characters to manipulate the structure of an HTTP request. This allows an attacker who can influence the outbound headers to inject arbitrary HTTP headers into the CONNECT request sent to the proxy server.Recommendations
Update to version 4.1.133.Final or newer.
Update to version 4.2.13.Final or newer.
As a temporary workaround, restrict access to the
outboundHeaders variable or ensure that any user-supplied data passed to the HttpProxyHandler constructor is strictly sanitized to remove CRLF characters.Exploit
Fix
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Weakness Enumeration
Related Identifiers
Affected Products
Linuxmint
Netty
Ubuntu