HTTP Response Splitting Affecting std/net/http package, versions <1.19.11>=1.20.0-0 <1.20.6
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-GOLANG-STDNETHTTP-14548601
- published6 Jan 2026
- disclosed11 Jul 2023
- creditBartek Nowotarski
Introduced: 11 Jul 2023
CVE-2023-29406 (opens in a new tab)How to fix?
Upgrade std/net/http to version 1.19.11, 1.20.6 or higher.
Overview
std/net/http is a Go standard library package std/net/http
Affected versions of this package are vulnerable to HTTP Response Splitting.
Go Vulnerability Report:
The HTTP/1 client does not fully validate the contents of the Host header. A maliciously crafted Host header can inject additional headers or entire requests.With fix, the HTTP/1 client now refuses to send requests containing an invalid Request.Host or Request.URL.Host value.