Chris O'Connell wrote: > I've been using DNSENUM.PL via BackTrack to do some information gathering > on my work's network.
Never heard of it, but looks like Dnsenum is documented here: http://code.google.com/p/dnsenum/ The purpose of Dnsenum is to gather as much information as possible about a domain. The program currently performs the following operations: 1) Get the host's addresse (A record). 2) Get the namservers. 3) Get the MX record. 4) Perform axfr queries on nameservers and get BIND versions... 5) Get extra names and subdomains via google scraping (google query = "allinurl: -www site:domain"). 6) Brute force subdomains from file, can also perform recursion on subdomain that have NS records. 7) Calculate C class domain network ranges and perform whois queries on them. 8) Perform reverse lookups on netranges... 9) Write to domain_ips.txt file ip-blocks. > So, not all of my DNS sub domains show up in a simple scan. (Lets set aside the "subdomain" terminology discussion. In my experience the term is often used even for domains that aren't delegated, which is likely a misuse of the term.) My guess would be that Dnsenum is getting its initial list by looking at names returned as a side effect of other queries. While zone transfers used to be readily accessible, as Rich said they've been largely disabled for security reasons (and at one time to avoid security holes in BIND). However, that restriction might be IP sensitive, and you might be allowed to do a zone transfer from your own LAN's IP range. You can try playing around with a tool like 'dig' to explore this further yourself. DNS is like a file system directory where you don't have permission to list the directory contents, but if you know the file name you can access the file contents. I'm assuming their brute force option simply goes through a list of common names, looking to see if each exists. But as implied by items #1 through #3 above, DNS intentionally reveals some information in order to make it useful. Disabling zone transfers is an attempts to hide the particulars within a zone, but it is imperfect at best, as this information often leaks out through other means (mail headers, for example). One possibility is to scan through the range of IP addresses used by your target and do reverse (PTR) queries on each IP (#8 above). Of course lots of DNS entries lack corresponding PTR records, so that may not turn up much. The source for Dnsenum can be viewed here: http://code.google.com/p/dnsenum/source/browse/trunk/dnsenum.pl?r=2 and it looks like if you run it in verbose mode it'll tell you a bit more about what queries it is performing. The best way to answer this question would be to obtain your zone file from whoever maintains your DNS and look at how the records vary between the ones that Dnsenum finds and the ones it can't. -Tom -- Tom Metro Venture Logic, Newton, MA, USA "Enterprise solutions through open source." Professional Profile: http://tmetro.venturelogic.com/ _______________________________________________ Discuss mailing list Discuss@blu.org http://lists.blu.org/mailman/listinfo/discuss
