CVE-2026-100663: Netty's HTTP/3 codec (io.netty:netty-codec-http3) from 4.2.2.Final through 4.2.17.Final does not special-case HTTP/1 CONNECT authority-form request-targets when converting HTTP/1 messages to HTTP/3 in HttpConversionUtil.
What it means
NIST National Vulnerability Database ha pubblicato CVE-2026-100663. La rilevanza va confermata rispetto alle tecnologie effettivamente in uso.
Why it matters
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Recommended actions
- Confermare l'applicabilita consultando la fonte ufficiale e l'inventario asset.
- Pianificare mitigazione o aggiornamento secondo criticita e rischio di interruzione.
Translation in progress
The official content is available in the original language. The Italian version will be published once automated checks are complete.
Text acquired from the source
Netty's HTTP/3 codec (io.netty:netty-codec-http3) from 4.2.2.Final through 4.2.17.Final does not special-case HTTP/1 CONNECT authority-form request-targets when converting HTTP/1 messages to HTTP/3 in HttpConversionUtil.toHttp3Headers. The authority-form target (e.g., "CONNECT trusted.example:443") is parsed as a URI, so its host is emitted as :scheme, :path is set to "/", and the HTTP/1 Host header is used as :authority; if no Host header is present the CONNECT target is dropped. In a Netty-based HTTP/1-to-HTTP/3 proxy or gateway, a remote client can send a CONNECT request whose Host header names a different authority than the request-target, producing a malformed HTTP/3 CONNECT whose tunnel :authority is attacker-controlled. This can bypass tunnel allow-lists, egress policy, backend selection, or audit controls that validate the HTTP/1 CONNECT request-target before forwarding over HTTP/3. The issue is fixed in 4.2.18.Final.
- Source
- NIST National Vulnerability Database
- Publishing entity
- NIST National Vulnerability Database
- Entity type
- National authority
- Area
- North America · US
- Original language
- en · translation in preparation
- Publication
- 26/09/2026 16:16
- CVE
- CVE-2026-100663
- Classification
- High
- Stated country
- US
Affected products and versions
The official sources queried do not yet expose a list of affected versions. No automatic inference is made.