nmap lacks full IPv6 support: IPv6 hosts incorrectly reported down

[Kasper Dupont]

When trying to scan an IPv6 host I got this error:

Starting Nmap 5.21 ( http://nmap.org ) at 2012-05-23 11:34 CEST
Note: Host seems down. If it is really up, but blocking our ping probes, try -PN
Nmap done: 1 IP address (0 hosts up) scanned in 3.26 seconds

The host is responding to pings, but nmap never send any pings to the host. Nmap only send a few TCP packets to the host, however this particular host did not have a TCP stack and does not reply to TCP packets.

I don't know if this bug is fixed by upstream updates, but since nmap 6 has been released and has lots of IPv6 updates it is not unlikely that it has been fixed upstream.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: nmap 5.21-1.1ubuntu1
ProcVersionSignature: Ubuntu 3.2.0-24.38-generic 3.2.16
Uname: Linux 3.2.0-24-generic i686
NonfreeKernelModules: nvidia
ApportVersion: 2.0.1-0ubuntu7
Architecture: i386
Date: Wed May 23 11:50:16 2012
EcryptfsInUse: Yes
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Release i386 (20110427.1)
ProcEnviron:
 LANGUAGE=en_US:en
 TERM=xterm
 PATH=(custom, user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: nmap
UpgradeStatus: Upgraded to precise on 2012-05-08 (14 days ago)

[James Page (james-page)]

Hi Kasper

Thanks for taking the time to report this bug in Ubuntu.

Please could you provide the command line options you are passing to nmap during this scan.

Marking 'Incomplete' pending your response - please set back to 'New' once you have provided the requested information.

Thanks

[James Page (james-page)]

I also see this when trying to UDP ping IPv6 hosts:

Sorry, UDP Ping (-PU) only works if you are root (because we need to read raw responses off the wire) and only for IPv4 (cause fyodor is too lazy right now to add IPv6 support and nobody has sent a patch)

[James Page (james-page)]

Looks like this will be fixed in nmap 6 'which has full IPv6 support'

Marking Confirmed

[pi-rho (pi-rho)]

This is confirmed fixed in the new upstream release 6.00 (documented at http://nmap.org/6/#changes-ipv6)

[Samuel Henrique (samueloph)]

Full IPV6 support since nmap 6.