What does Nuclei do when it starts?

[stefanocoding]

Hi community.
If I run Nuclei with a IPv6 subnet like nuclei -u "2620:134:b000::/40", I only see the Nuclei banner indefinitely. No idea what's going on.
What is it doing when it starts?
Thanks in advance for the answers.

[ehsandeep]

@stefanocoding, the tool is attempting to process the input. specifically, it fails when trying to expand the IPv6 range 2620:134:b000::/40 using mapcidr, causing it to hang. Are you actually intending to scan this range?

[stefanocoding]

@ehsandeep thank you for the explanation! No, I don't intend to scan that range. I noticed the issue when testing a template with a list of random targets from bug bounties programs which had an IPv6 subnet there. I removed it and everything worked.
Is it possible to get a warning if it fails or something like that? Because I tried the verbose flag but it didn't provide more information.

[ehsandeep]

Thanks and yes it's an edge case and error handling can be improved.

[stefanocoding]

🙂 👍