Penetration Testing mailing list archives
Re: Port Scanning Issues
From: "Lee Lawson" <leejlawson () gmail com>
Date: Tue, 26 Jun 2007 08:54:05 +0100
Port scanning is not an exact science, although it should be. With regard to UDP scanning, a port is determined as open if it does not respond to probe attempts. This means that if it responds with an ICMP port unreachable message, it's closed, it no response is received, it is thought to be open. There are a number of reasons that causes a lack of response to a UDP scan, such as network issues, firewalls, luck! I find that UDP scanning, especially over the Internet, is likely to cause conflicting results. What do you get for TCP results? Are you scanning on the LAN or over the Internet? Have you tried nmap? Something worth trying as an exercise is to identify all of the open ports on the local, target system (if you have access to it!). You can use a number of tools to do this, but I like fport. It's a small command line tools that lists the PID, port, protocol and parent process. Run this tool and then compare the locally gathered results to the port scanners. On 25 Jun 2007 21:59:58 -0000, crumdub12 () gmail com <crumdub12 () gmail com> wrote:
A Chairde, Havin, some issues with scanning stacks on my system. 1. Using Superscan4 , I scan stack UDP-TCP 1-65534 , Sometimes I get no ports open , another time I get 49159 UDP Ports open, only get port report, no attempt made to open any ports ... , when get open ports , I always get 49159 UDP Ports ...... , use the scanner at 250msecs , takes around 16 hours to finish. 2. Using Languard, Nessus and Retina , get different scans from each tool, any ideas why, how do I find out real ports open.. differences can be 10,000 ports ------------------------------------------------------------------------ This List Sponsored by: Cenzic Are you using SPI, Watchfire or WhiteHat? Consider getting clear vision with Cenzic See HOW Now with our 20/20 program! http://www.cenzic.com/c/2020 ------------------------------------------------------------------------
-- Lee J Lawson leejlawson () gmail com "Give a man a fire, and he'll be warm for a day; set a man on fire, and he'll be warm for the rest of his life." "Quidquid latine dictum sit, altum sonatur." ------------------------------------------------------------------------ This List Sponsored by: Cenzic Are you using SPI, Watchfire or WhiteHat? Consider getting clear vision with Cenzic See HOW Now with our 20/20 program! http://www.cenzic.com/c/2020 ------------------------------------------------------------------------
Current thread:
- Port Scanning Issues crumdub12 (Jun 25)
- Message not available
- Port Scanning Issues Steinar Watne (Jun 26)
- Message not available
- Re: Port Scanning Issues sherwyn . williams (Jun 26)
- Re: Port Scanning Issues Jamie Riden (Jun 26)
- Re: Port Scanning Issues Vijay (Jun 26)
- Re: Port Scanning Issues Lee Lawson (Jun 26)
- <Possible follow-ups>
- Re: Port Scanning Issues ebk_lists (Jun 26)