cve.bz

CVE-2026-42578

2.9 lowEPSS 1.1%

Low (2.9) in netty netty. EPSS 1.1% chance of exploitation in the next 30 days. Fixed in io.netty:netty-handler-proxy 4.1.133.Final, 4.2.13.Final.

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.

Severity

CVSS 4.0

2.9 low
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

CVSS 3.1

7.5 high
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
EPSS
1.1% chance of exploitation in the next 30 days; higher than 64% of CVEs (scores of 2026-10-31)
CWEs
CWE-113, CWE-93
Published
Modified
Record from
the NVD, synced

Affected

Packages (OSV)

AdvisoryEcosystemPackageAffectedFixed in
GHSA-45q3-82m4-75jrMavenio.netty:netty-handler-proxy<4.1.133.Final4.1.133.Final
GHSA-45q3-82m4-75jrMavenio.netty:netty-handler-proxy>=4.2.0.Alpha1 <4.2.13.Final4.2.13.Final

References

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