CVE-2026-94439
highpriority · track · 0EPSS 0.004 · 36 %ileDEFRUSEPSS · scored 2026-10-28
When an HTTP server handler sends a 2xx response to an HTTP/1 CONNECT request and returns without hijacking the connection, the server improperly continues to read and serve requests from the connection. Since a 2xx response to an HTTP/1 CONNECT converts the connection into a tunnel, the server should not treat the connection as continuing to contain HTTP. The impact of this misbehavior is mostly limited to potential request smuggling, where an intermediate proxy considers the data on the connection to be tunneled and the server considers it to be HTTP.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–7.5
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (13)
Products and version ranges known to be affected.
advisories (4)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-3841Golang Go: Mehrere SchwachstellenDeutsch2026-10-08csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Golang Go ausnutzen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen, um Daten zu manipulieren und um Sicherheitsvorkehrungen zu umgehen.
- BIT-golang-2026-94439HTTP/1 server connection desynchronization after 2xx CONNECT response in net/http2026-10-16vendor · osvUS
When an HTTP server handler sends a 2xx response to an HTTP/1 CONNECT request and returns without hijacking the connection, the server improperly continues to read and serve requests from the connection. Since a 2xx response to an HTTP/1 CONNECT converts the connection into a tunnel, the server should not treat the connection as continuing to contain HTTP. The impact of this misbehavior is mostly limited to potential request smuggling, where an intermediate proxy considers the data on the connection to be tunneled and the server considers it to be HTTP.
- CERTFR-2026-AVI-1385Multiples vulnérabilités dans les produits VMwareFrançais2026-10-26vendor · certfrFR
- GO-2026-6613HTTP/1 server connection desynchronization after 2xx CONNECT response in net/http2026-10-08vendor · osvUS
When an HTTP server handler sends a 2xx response to an HTTP/1 CONNECT request and returns without hijacking the connection, the server improperly continues to read and serve requests from the connection. Since a 2xx response to an HTTP/1 CONNECT converts the connection into a tunnel, the server should not treat the connection as continuing to contain HTTP. The impact of this misbehavior is mostly limited to potential request smuggling, where an intermediate proxy considers the data on the connection to be tunneled and the server considers it to be HTTP.
also known as (2)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (4) nvd
External citations — patches, advisories, analysis.
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