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Different results in output -o S and -o J (simple and json)

Open marcelo321 opened this issue 3 years ago • 3 comments

Hello,

After 2 hours of testing I found out that i am getting different results from simple output that json output and it is getting me crazy.

So i am trying to get NOERROR responses like:

...-o J 2> /dev/null | jq -r 'select(.status=="NOERROR") .name' and I get like 50 results. with only 6 being valid (only 6 of the total are valid).

Running the same command but like -o S 2> /dev/null | awk '{print $1}' | anew and I get only the 6 valid, and the command is working as expected.

Then I analyzed the json output and noticed that I am getting a looot of noerror responses that are incorrect, but for some reason that isn't happening with simple output.

I made the tests against same hosts and with the same resolvers countless of times and getting really different responses.

marcelo321 avatar Feb 18 '21 21:02 marcelo321

So I am running it against 200 hosts, with only 1.1.1.1 and 8.8.8.8 resolvers. I am only changing the output flag to json, and automatically get multiple false positives that I was no getting them with simple output.

If changing the 200 hosts to a bigger list, the false positives increase a lot making massdns unusable for me

marcelo321 avatar Feb 18 '21 21:02 marcelo321

Look if answers as a list are present inside the data for the given domain within the JSON output to filter false positives.

iamsonidarshan avatar Aug 01 '21 01:08 iamsonidarshan

Use this instead: https://github.com/blechschmidt/massdns/blob/master/scripts/massdnsA.jq

EDIT: If I'm misunderstanding your issue, please attach your list of hosts and resolvers, I'm happy to try quickly to reproduce the issue

mzpqnxow avatar Aug 26 '21 18:08 mzpqnxow