Cloudflare is using "Black Lies".
For an NXDOMAIN, they always return \000.(the missing name) as the next name.
Thus the \0 will cause the invalid escape in JSON format
For example, the result of querying cloudflare.com@1.1.1.1CNAME
"next_domain_name":"\000.cloudflare.com."
Although the answer part is empty, the authority part will contain the response of NSEC, and cause the invalid escape due to \0
It's just an example of known invalid escape, there might be other possible responses that cause the same issue.
Cloudflare is using "Black Lies". For an NXDOMAIN, they always return \000.(the missing name) as the next name. Thus the
\0
will cause the invalid escape in JSON formatFor example, the result of querying
cloudflare.com
@1.1.1.1
CNAME
"next_domain_name":"\000.cloudflare.com."
Although the answer part is empty, the authority part will contain the response of NSEC, and cause the invalid escape due to\0
It's just an example of known invalid escape, there might be other possible responses that cause the same issue.