cvedb.io
CVE-2026-59900
UNKNOWN · CVSS n/a
EPSS exploitation probability: 0%
Published 2026-07-29T18:16:56.320 · Last modified 2026-07-29T18:16:56.320

Summary

Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.136.Final and 4.2.16.Final, Netty's HTTP/2-to-HTTP/1.x translation layer (`Http2StreamFrameToHttpObjectCodec` and `InboundHttp2ToHttpAdapter`) fails to deduplicate or validate `Host` headers when an HTTP/2 client supplies both the `:authority` pseudo-header and a literal `host` header in a single HEADERS frame. The translator maps `:authority` to `Host` and separately copies the literal `host` header, producing an `HttpRequest` object containing two `Host` headers with attacker-controlled differing values. This issue has been fixed in versions 4.1.136.Final and 4.2.16.Final.

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.