狗爺語錄

It had been some while ago since last time I was using netcat for Windows. Indeed it is always an invaluable tool, indispensable for any network admin or computer security workers. So it is kind of shocked when the official site for win32 netcat, http://www.vulnwatch.org/netcat/, is not even available on Google cache.

The only choice left is to search for any archived netcat on the net — that’s a job easier said than done, as there is little way for one to tell which version is authentic. Luckily, I’ve got one on my work machine, and after comparing with some other archived copies floating around on internet, I’m able to confidently say this copy is the authentic 1.11 (newest) version for Win32.

It can be downloaded from my machine.

MD5: a2d3026b4630789247abf07aa3986d7a697cf4cd
SHA1: 52eb68a2911a04f7437beb0c8b50a505356673441f92b4795b0249504eaa7d36

This page on pintday has done a pretty good job at introducing history of win32 netcat and a few netcat variants; sadly its link to 1.11 version is in fact 1.1 instead, which is known to contain buffer overflow vulnerability. Even after guessing and fetching the correct file name… no, it’s STILL incorrect. The pintday version differs only by one trivial line:

--- printday/netcat.c	2004-12-28 11:06:16.000000000 +0800
+++ vulnwatch/netcat.c	2004-12-29 13:07:04.000000000 +0800
@@ -2045,7 +2045,7 @@
 int helpme()
 {
   o_verbose = 1;
-  holler ("[v1.10 NT]\n\
+  holler ("[v1.11 NT www.vulnwatch.org/netcat/]\n\
 connect to somewhere:	nc [-options] hostname port[s] [ports] ... \n\
 listen for inbound:	nc -l -p port [options] [hostname] [port]\n\
 options:");

Probably this is the only difference between 1.10 and 1.11: just a banner. But still, forget the pintday versions.

Searching on filewatcher is fruitless too. Compare the list of nc11nt.zip and the list of nc111nt.zip: not only the list of nc111nt.zip being significantly shorter, but large portion of the link is unreachable as well.

So the versions found to match are:

1. From Hackosis (with a backup copy from Jon Craton)
2. From Jesse Morgan (only nc.exe binary is available; anyway the binary matches after comparison)
3. Yet another copy

I noticed one version significantly different; this one is purported to be compiled using UWIN, resulting in smaller binary. That one looks like 1.10, according to strings output.

Too bad that netcat looks like an orphaned child, no matter on Windows or on Unix. Luckily there are better spin-offs like cryptcat and ncat — no, I’ll take back my word. More than 2 years without a release. Are they abandoned too, or they are so stable that no more release is needed?