DNS
Mock 16 BADVERS/BADSIG Response
Bad OPT Version or TSIG Signature Failure. Either the EDNS version in the OPT record is not supported, or the TSIG signature on the message failed verification.
View full reference →1 HTTP Response
HTTP/1.1 16 BADVERS/BADSIG Content-Type: application/json Date: Tue, 25 Feb 2026 12:00:00 GMT
2 Test with curl
curl -i https://httpbin.org/status/16
3 Return 16 BADVERS/BADSIG in Your Framework
django
from django.http import HttpResponse
def my_view(request):
return HttpResponse(status=16) # BADVERS/BADSIG
flask
from flask import Flask
app = Flask(__name__)
@app.route("/endpoint")
def my_endpoint():
return "", 16 # BADVERS/BADSIG
fastapi
from fastapi import FastAPI
from fastapi.responses import Response
app = FastAPI()
@app.get("/endpoint")
def my_endpoint():
return Response(status_code=16) # BADVERS/BADSIG
express.js
// Express.js
app.get('/endpoint', (req, res) => {
res.sendStatus(16); // BADVERS/BADSIG
});
spring boot
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;
@RestController
public class MyController {
@GetMapping("/endpoint")
public ResponseEntity<Void> myEndpoint() {
return ResponseEntity
.status(16) // BADVERS/BADSIG
.build();
}
}
go net/http
package main
import "net/http"
func myHandler(w http.ResponseWriter, r *http.Request) {
w.WriteHeader(16) // BADVERS/BADSIG
}
ruby on rails
class MyController < ApplicationController
def my_action
head :badvers/badsig
end
end
asp.net core
// ASP.NET Core Minimal API
app.MapGet("/endpoint", () =>
Results.StatusCode(16) // BADVERS/BADSIG
);