projectdiscovery/nuclei · error

malformed raw http response

Error message

malformed raw http response

What it means

Error "malformed raw http response" thrown in projectdiscovery/nuclei.

Source

Thrown at pkg/protocols/offlinehttp/read_response.go:30

// readResponseFromString reads a raw http response from a string.
func readResponseFromString(data string) (*http.Response, error) {
	// Check if "data" contains RFC compatible Request followed by a response
	br := bufio.NewReader(strings.NewReader(data))
	if req, err := http.ReadRequest(br); err == nil {
		if resp, err := http.ReadResponse(br, req); err == nil {
			return resp, nil
		}
	}

	// otherwise tries to patch known cases such as http minor version
	var final string
	if strings.HasPrefix(data, "HTTP/") {
		final = addMinorVersionToHTTP(data)
	} else {
		lastIndex := strings.LastIndex(data, "HTTP/")
		if lastIndex == -1 {
			return nil, errors.New("malformed raw http response")
		}
		final = data[lastIndex:] // choose last http/ in case of it being later.

		final = addMinorVersionToHTTP(final)
	}
	return http.ReadResponse(bufio.NewReader(strings.NewReader(final)), nil)
}

// addMinorVersionToHTTP tries to add a minor version to http status header
// fixing the compatibility issue with go standard library.
func addMinorVersionToHTTP(data string) string {
	matches := noMinor.FindAllStringSubmatch(data, 1)
	if len(matches) == 0 {
		return data
	}
	if len(matches[0]) < 2 {
		return data
	}

View on GitHub (pinned to 265b3a3dec)

When it happens

Trigger: Thrown at pkg/protocols/offlinehttp/read_response.go:30 when the library encounters an invalid state.

Common situations: See trigger scenarios.

Understand the failure class

• Parsing and encoding errors: unexpected token, malformed input — why parsers reject input and how to find the real culprit.

AI-assisted analysis of projectdiscovery/nuclei@265b3a3dec (2026-08-15). Data as JSON: /api/errors/adba538133168328. Report an issue: GitHub.