Nmap Development mailing list archives
nmap -sP doesn't really send ICMP packets?
From: "Burton Windle" <burtonwindle () gmail com>
Date: Tue, 6 Feb 2007 10:55:34 -0500
Hello. nmap 4.20, complied locally on a Debian Testing system running Linux kernel 2.6.20. When doing an nmap -sP (to scan for machines that respond to ICMP Echo packets) nmap was reporting that a certain host was down. In fact, the machine responds to ICMP pings (Type 8, and sends back Type 0), but TCP/80 is filtered (no RST, nothing) In doing packet sniffs, it appears that "nmap -sP host" will not actually do an ICMP ping scan, but instead send *only* a packet to TCP/80 to the host; if that fails, it reports it down. Is this a bug or a feature? the man page says "The -sP option sends an ICMP echo request *and* a TCP packet to port 80 by default." However I am only seeing TCP/80 and no ICMP. This is trivial to reproduce; I have tcpdump packet traces to verify. -- Burton _______________________________________________ Sent through the nmap-dev mailing list http://cgi.insecure.org/mailman/listinfo/nmap-dev Archived at http://SecLists.Org
Current thread:
- nmap -sP doesn't really send ICMP packets? Burton Windle (Feb 06)
- Re: nmap -sP doesn't really send ICMP packets? Fyodor (Feb 06)