On Tue, Aug 05, 2003 at 12:12:39AM -0700, Richard P. Koett wrote: > >>Naveen Pareek wrote: > >> I want to scan my company's private network. This will be external > >> scan. There is one router with one public IP. Through that IP i want > >> to scan private network of my company. Is it possible then how? > >> If i'll put target as 192.168.0.0/24 then it will not scan because > this > >> IP is range is invalid. If i'll put 202.145.16.0/29 then it will > scan > >> only subnet of 202.145.16.0 but i want to scan 192.168.0.0 > >> through this router ip address. (IP addresses are changed due to > >> security reason.) Please help me out in this issue. > > Carl Houseman wrote: > > It's not possible. That is the nature of NAT. If you want to know > > the security vulnerabilities of the internal network _as seen by the > > outside world_, you scan the single public IP with a wide range of > > ports and all possible ping methods. > > Actually it *may* be possible to scan the internal IPs' from outside > the gateway. If the machine you scan from is plugged in to the same > subnet as the external interface of the router and is configured with a > static route to the internal network that uses the router as it's > gateway, > then the router *might* pass the packets through to the internal > network. It depends on how the router is configured. Even though > nobody is supposed to route RFC1918 addresses it is possible to > do so. I don't really see what the point of all this would be, however. > > Naveen,
The only way you can scan RFC1918 addresses from a host on the external Internet would be to setup a VPN between your external router (the one with the public IP) and a box on your end. How you set it up (IPSec, PPTP, SSL VPN) is somewhat inconsequential. The point is that all traffic from the scanning box is routed through the tunnel to the router endpoint. Ido -- =============================================================================== Ido Dubrawsky, CISSP E-mail: [EMAIL PROTECTED] Network Security Architect [EMAIL PROTECTED] dubrawsky.org 500 Hermleigh Rd Silver Spring, MD. 20902 (301) 651-5441 (cell) ===============================================================================
