CVE-2023-29406
MediumSummary
The Go 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. The fix prevents sending requests with invalid Request.Host or Request.URL.Host values.
Risk Assessment
The risk involves potential request smuggling or header injection attacks, which could compromise communication integrity, enable session hijacking, or bypass security controls.
Recommendation
Immediately update the Go library to a patched version (e.g., 1.20.6 or 1.19.11) and recompile all applications using the HTTP/1 client.
Other vulnerabilities in Go
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- CVE-2023-39325High
A vulnerability in Go's HTTP/2 implementation allows a malicious client to rapidly create and reset requests, causing excessive server resource consumption. Although the number of concurrent streams is limited by MaxConcurrentStreams, resetting requests enables the attacker to continuously send new requests.
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The Go HTTP client drops sensitive headers (e.g., Authorization) after a cross-domain redirect, but may re-send them on a subsequent same-domain redirect, posing a potential data leak risk.
- CVE-2023-45290Medium
When parsing a multipart form in Go, limits on the total form size were not applied to memory consumed while reading a single form line. This allows an attacker to send a malicious request causing excessive memory consumption.
- CVE-2023-45283High
The filepath package in Go does not recognize paths with a \??\ prefix as special. On Windows, a path starting with \??\ is equivalent to a path starting with \\?\ and can be used to access arbitrary system locations.
- CVE-2024-34155Medium
A vulnerability in the Go standard parser causes a panic when processing source code with deeply nested literals. The issue stems from stack exhaustion during recursive parsing.
- CVE-2025-0913Medium
The vulnerability in the os.OpenFile implementation in Go causes different behavior on Unix and Windows systems when the target path is a dangling symlink. On Unix, the O_EXCL flag prevents following symlinks, while on Windows the function may follow the symlink to a nonexistent location.
Original NVD description (English source)
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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

