Security Basics mailing list archives
RE: Basic firewall filtering question
From: "Ferino Mardo" <RMardo () ALJOMAIHBEV com>
Date: Tue, 27 Jul 2004 20:47:45 +0300
But wouldn't that break some required connections from the AD/DC? Don't they connect thru null sessions?
-----Original Message----- From: Gethin Jones [mailto:gethinj () gethin net] Sent: Monday, July 26, 2004 9:54 PM To: Ferino Mardo; security-basics () securityfocus com Subject: Re: Basic firewall filtering question Dear All, The best way to secure these 'holes' in NETBIOS security is to put security policies in place that do not allow 'NULL' account access to NETBIOS shares such as C$, ADMIN$ and IPC$. If you start blocking access to these shares completely you will run into all sorts of problems. Have a look :-) Windows 2000 1.. Open up the Domain Policy. 2.. Select Security Settings 3.. Select Local Policies 4.. Select Security Options. 5.. Choose "Additional restrictions of anonymous connections" in the policy pane and from the pull down menu labelled "Local policy setting", select "No access without explicit anonymous permissions. Click OK and reboot the machine. Windows XP & Windows 2003 1.. Open the Domain Policy 2.. Select Security Settings 3.. Select Local Policies 4.. Select Security Options. Make sure that BOTH the following options are enabled: Network Access: Do not allow anonymous enumeration of SAM accounts. Network Access: Do not allow anonymous enumeration of SAM accounts and shares. The Windows XP & 2003 settings do not completely fix the problem as some aspects of the policies have not been added by Microsoft yet. But as Microsoft releases patches for their servers they will incorporate the correct settings. Best Regards Gethin
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Current thread:
- Basic firewall filtering question Ferino Mardo (Jul 26)
- Re: Basic firewall filtering question Gethin Jones (Jul 26)
- Re: Basic firewall filtering question mike (Jul 26)
- <Possible follow-ups>
- RE: Basic firewall filtering question Gallina, Michael (Jul 27)
- RE: Basic firewall filtering question Ferino Mardo (Jul 28)
- RE: Basic firewall filtering question Ferino Mardo (Jul 29)