BUG: Flag banners is not reliable.

[matejsmycka]

I have encountered a case where banners do not output anything.

Environment:

• Ubuntu Noble 6.8.0-83-generic
• Masscan via APT

Masscan version 1.3.2 ( https://github.com/robertdavidgraham/masscan )
Compiled on: Feb  2 2021 11:13:27
Compiler: gcc 10.2.1 20210130
OS: Linux
CPU: unknown (64 bits)
GIT version: unknown

[mzpqnxow]

I have encountered a case where banners do not output anything.

Environment:

• Ubuntu Noble 6.8.0-83-generic
• Masscan via APT

Masscan version 1.3.2 ( https://github.com/robertdavidgraham/masscan )
Compiled on: Feb  2 2021 11:13:27
Compiler: gcc 10.2.1 20210130
OS: Linux
CPU: unknown (64 bits)
GIT version: unknown

Reference the documentation. Specifically, --adapter-port

Also, recommend you always use masscan from git master

[matejsmycka]

Thank you

[matejsmycka]

Sorry for bothering, I did what the docs suggested:

sudo iptables -I INPUT -p tcp --dport 61000:62000 -j DROP

sudo masscan <IP> -p3580 --banners --adapter-port 61000 --wait 15
Starting masscan 1.3.2 (http://bit.ly/14GZzcT) at 2025-11-13 12:55:14 GMT
Initiating SYN Stealth Scan
Scanning 256 hosts [1 port/host]
Discovered open port 3580/tcp on <IP>                              
Discovered open port 3580/tcp on <IP>                        
Discovered open port 3580/tcp on <IP>                        
Discovered open port 3580/tcp on <IP>

There are no banners in the output.

ubuntu@pentest01:~$ curl -I <IP>:3580
HTTP/1.1 404 Not Found
Connection: Keep-Alive
Server: Embedthis-http
ETag: "0-0-5aa15000"

But when I curl, there are definitely some things that should be in the banner.

Is there something I am missing?

Here are servers that do not work for me https://www.shodan.io/search?query=http.component%3A%22EmbedThis+Appweb%22+port%3A3580

[mzpqnxow]

You may find issue #120 helpful

[matejsmycka]

I understand everything, thank you