Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
AV AC AT PR UI VC VI VA CVSS EPSS %ile KEV N L P N N N L N 2.9 .0106 62.0 —
AFFECTED Product Versions Fixed netty >= 4.2.0.Alpha1, < 4.2.13.Final – —
TIMELINE Apr 28 Reserved by GitHub_M May 13 Published (CNA: GitHub_M) Aug 13 EXPLOIT PUBLISHED — CVE-2026-42578 (netty). Public exploit reference added.
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.
| Date | Event | Detail |
|---|---|---|
| April 28, 2026 | Reserved | Reserved by GitHub_M |
| May 13, 2026 | Published | Published (CNA: GitHub_M) |
| August 13, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-42578 (netty). Public exploit reference added. |
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
|---|---|---|---|---|
| netty | netty | — | >= 4.2.0.Alpha1, < 4.2.13.Final | — |
Authoritative record: CVE-2026-42578 at cve.org
Vendors: netty
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-42578 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.