Penetration Testing mailing list archives
Re: [PEN-TEST] Changing MAC address on Win2k
From: Peter Van Epp <vanepp () SFU CA>
Date: Tue, 13 Feb 2001 12:16:35 -0800
Changing the arp cache entry will not change the MAC address the card is using, it will only change the MAC address associated with the IP in the arp cache. As someone mentioned you need to convince the card driver to change the MAC address. Failing that you need to find the I/O address of the Ethernet chip where the MAC address is written. This is generally trivial using debug and the initialization ROM on the card. I always have a good laugh when a vendor tells me that "you can't change MAC addresses so our product (which depends on MAC addresses) is secure". Its never taken me more than 1/2 an hour to find the necessary ports on the Ethernet chip (and your CPU writes the MAC address from prom/flash to the Enet chip during BIOS boot up in all cases execpt where there is a CPU on the Enet card which is quite rare). Not all salesbeings seem to understand this however ... One note: when doing this make sure you use a valid MAC address (such as one stolen from a card which is disconnected and in your hand) because duplicate MAC addresses on a network will cause excitement. Peter Van Epp / Operations and Technical Support Simon Fraser University, Burnaby, B.C. Canada
Hi all! :) Is Working only in Win2k ?? Because i try it here in my Nt 4.0 +SP6a ...but i didn't had error in arp command...but didn't work...look: ConfiguraÆo de IP do Windows NT Nome do host . . . . . . . . . . : nt_hadrion.hadrion.com Servidores DNS . . . . . . . . . : Tipo de n¢ . . . . . . . . . . . : H¡brida Identificador de escopo NetBIOS. : Roteamento de IP ativado . . . . : Sim Proxy WINS ativado . . . . . . . : NÆo ResoluÆo NetBIOS usa DNS. . . . : NÆo Ethernet adaptador E100B1: DescriÆo. . . . . . . . . . . . : Intel EtherExpress PRO PCI Adapter Endereo f¡sico. . . . . . . . . : 00-10-DC-0D-40-27 DHCP ativado . . . . . . . . . . : NÆo Endereo IP. . . . . . . . . . . : 192.168.151.100 M scara de sub-rede. . . . . . . : 255.255.255.0 Gateway padrÆo . . . . . . . . . : 192.168.151.1 Servidor WINS prim rio . . . . . : 120.120.120.2 Ethernet adaptador NdisWan4: DescriÆo. . . . . . . . . . . . : NdisWan Adapter Endereo f¡sico. . . . . . . . . : 00-00-00-00-00-00 DHCP ativado . . . . . . . . . . : NÆo Endereo IP. . . . . . . . . . . : 0.0.0.0 M scara de sub-rede. . . . . . . : 0.0.0.0 Gateway padrÆo . . . . . . . . . : Then i do to test: arp -s 192.168.151.100 00-10-DC-0D-40-40 changing only the ultimate 2 numbers of mac...and it didn't show-me error...but when i verify my mac appear igual before! look (same mac): Ethernet adaptador E100B1: DescriÆo. . . . . . . . . . . . : Intel EtherExpress PRO PCI Adapter Endereo f¡sico. . . . . . . . . : 00-10-DC-0D-40-27 DHCP ativado . . . . . . . . . . : NÆo Endereo IP. . . . . . . . . . . : 192.168.151.100 M scara de sub-rede. . . . . . . : 255.255.255.0 Gateway padrÆo . . . . . . . . . : 192.168.151.1 Servidor WINS prim rio . . . . . : 120.120.120.2 Thkz... until more! =) -----Mensagem original----- De: N0sferatu <satan () TM NET MY> Para: PEN-TEST () SECURITYFOCUS COM <PEN-TEST () SECURITYFOCUS COM> Data: Domingo, 11 de Fevereiro de 2001 23:47 Assunto: Re: [PEN-TEST] Changing MAC address on Win2k ; I don't really know whether this is correct but I have tried and found that the MAC address can be changed in Win2k by issuing this command : arp -s ip-of-the-computer mac-address though it might be wrong.. \ -----Original Message----- From: Penetration Testers [mailto:PEN-TEST () SECURITYFOCUS COM]On Behalf Of Parth Galen Sent: Monday, February 12, 2001 4:46 AM To: PEN-TEST () SECURITYFOCUS COM Subject: [PEN-TEST] Changing MAC address on Win2k I recently read in Pen-Test that the MAC could be changed in Win2k. I have looked on the web for info, and in the archives at Security Focus but can not find any "How To" information. Nothing on my system offers any obvious opportunity either. So, can anyone tell my how to change the MAC on Win2k. This has to do with better anonymity while doing Pen-Tests. It is nice to hop through proxies, but my MAC is always there to ID me. Specifically, I working in a multi-site company, and their ID (they tell me) is blocking my work based on MAC. Changing IP does not help. Thanks Much, Parth Get your small business started at Lycos Small Business at http://www.lycos.com/business/mail.html
Current thread:
- Re: [PEN-TEST] Changing MAC address on Win2k, (continued)
- Re: [PEN-TEST] Changing MAC address on Win2k N0sferatu (Feb 11)
- Re: [PEN-TEST] Changing MAC address on Win2k kevin Timm (Feb 11)
- Re: [PEN-TEST] Changing MAC address on Win2k Nelson Brito (Feb 13)
- Re: [PEN-TEST] Changing MAC address on Win2k Shoten (Feb 13)
- Re: [PEN-TEST] Changing MAC address on Win2k kevin Timm (Feb 11)
- Re: [PEN-TEST] Changing MAC address on Win2k Jeff Nathan (Feb 11)
- Re: [PEN-TEST] Changing MAC address on Win2k N0sferatu (Feb 11)
- Re: [PEN-TEST] Changing MAC address on Win2k Abe Getchell (Feb 11)
- Re: [PEN-TEST] Changing MAC address on Win2k Fulton L. Preston Jr. (Feb 12)
- Re: [PEN-TEST] Changing MAC address on Win2k Adrien de Beaupre (Feb 12)
- Re: [PEN-TEST] Changing MAC address on Win2k -=Quequero=- (Feb 13)
- Re: [PEN-TEST] Changing MAC address on Win2k sekure (Feb 13)
- Re: [PEN-TEST] Changing MAC address on Win2k Peter Van Epp (Feb 13)
- Re: [PEN-TEST] Changing MAC address on Win2k bacano (Feb 13)
- Re: [PEN-TEST] Changing MAC address on Win2k Alex Tibbles (Feb 13)
- Re: [PEN-TEST] Changing MAC address on Win2k Lars Gaarden (Feb 14)
- Re: [PEN-TEST] Changing MAC address on Win2k Peter Van Epp (Feb 14)
- Re: [PEN-TEST] Changing MAC address on Win2k Ryan Permeh (Feb 14)
- Re: [PEN-TEST] Changing MAC address on Win2k Peter Van Epp (Feb 13)
- Re: [PEN-TEST] Changing MAC address on Win2k Hugo Fortier (Feb 13)
- Re: [PEN-TEST] Changing MAC address on Win2k Olli Artemjev (Feb 14)
- Re: [PEN-TEST] bs (Feb 14)