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CVE-2021-33197 is an improper input-validation vulnerability in Go's net/http/httputil ReverseProxy. In Go releases before 1.15.13 and 1.16.x before 1.16.5, certain ReverseProxy configurations mishandle Connection headers when the first such header is empty. The proxy can then forward connection-specific headers, allowing an attacker to cause arbitrary HTTP headers to be removed.
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A flaw in Go's net/http/httputil ReverseProxy that can forward connection headers when the first header is empty. It affects installed Golang-related packages on Rocky Linux 8 covered by CIQ advisory crlsa-2021_4156.
A Go net/http/httputil ReverseProxy vulnerability that forwards connection headers when the first header is empty.
A Go net/http/httputil ReverseProxy flaw that forwards connection headers when the first connection header is empty.
A Go net/http/httputil ReverseProxy flaw that forwards connection headers when the first header is empty.
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Every observed campaign linking this CVE to a named adversary.
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Cross-references every affected SKU, including bundled OEM variants.
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