CVE-2026-94439
Description
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.
How to fix
- stdlib1.26.9, 1.27.2 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| stdlibGo | v < 1.26.9, 1.27.0-0 ≤ v < 1.27.2 | 1.26.9, 1.27.2 |
| microsoft azl3_golang_1.26.7-1 | No range specified | — |
| microsoft azl3_golang_1.27.1-1 | No range specified | — |
| microsoft azl3_golang_1.26.10-1 | No range specified | — |
| microsoft azl3_golang_1.27.3-1 | No range specified | — |
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