Please fill out the fields below so we can help you better. Note: you must provide your domain name to get help. Domain names for issued certificates are all made public in Certificate Transparency logs (e.g. crt.sh | example.com), so withholding your domain name here does not increase secrecy, but only makes it harder for us to provide help.
My domain is:
I ran this command:
certbot -d *.bc.n0w.cc --manual --preferred-challenges dns certonly
It produced this output:
Waiting for verification...
Cleaning up challenges
Failed authorization procedure. bc.n0w.cc (dns-01): urn:ietf:params:acme:error:unauthorized :: The client lacks sufficient authorization :: No TXT record found at _acme-challenge.bc.n0w.cc
The following errors were reported by the server:
Detail: No TXT record found at _acme-challenge.bc.n0w.cc
To fix these errors, please make sure that your domain name was
entered correctly and the DNS A/AAAA record(s) for that domain
contain(s) the right IP address.
My web server is (include version):
Portswigger.net's Burp Collaborator
It's a java application
The operating system my web server runs on is (include version):
Linux n0w 4.19.0-10-cloud-amd64 #1 SMP Debian 4.19.132-1 (2020-07-24) x86_64 GNU/Linux
My hosting provider, if applicable, is:
Route53 however the bc subdomain is running on this host, the Burp Collaborator
I can login to a root shell on my machine (yes or no, or I don't know):
I'm using a control panel to manage my site (no, or provide the name and version of the control panel):
no, I ssh onto the box
The version of my client is (e.g. output of
certbot --version or
certbot-auto --version if you're using Certbot):
rootn0w certbot --version
I'm unable to complete the DNS txt challenge with certbot and it seems the issue is the mixed-case query. If I query it manually using lower-case characters I the proper reply.
rootkali dig txt _acmE-ChAlLENGE.Bc.N0W.Cc +short
rootkali dig txt _acme-challenge.bc.n0w.cc +short