SCSC 555 Frank Li

 Introduction to Enumeration  Enumerate Microsoft OS  Enumerate *NIX OS  Enumerate NetWare OS (skip) 2

 Enumeration extracts information about: ◦ Resources or shares on the network ◦ User names or groups assigned on the network ◦ Last time user logged on ◦ User’s password  Enumeration is more intrusive than passive port scanning ◦ First need to determine OS of the target host  By Port scanning and footprinting ◦ E.g. NBT (NetBIOS over TCP/IP) is the tool for enumerating Microsoft OSs 3

 Using enumeration tool nbtscan ◦ Use nbtscan command to scan a range of IP addresses ◦ Example: nbtscan /24 4

 Introduction to Enumeration  Enumerate Microsoft OS  Enumerate *NIX OS 5

 Study OS history ◦ Knowing your target makes your job easier ◦ Many attacks that work for older Windows OSs still work with newer versions 6

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 Network Basic Input Output System (NetBIOS) ◦ Is a MS programming interface ◦ Allows computer communication over a LAN ◦ Used to share files and printers  NetBIOS names are computer names assigned to Windows systems ◦ Must be unique on a network ◦ Limit of 16 characters ◦ The last character (suffix) is reserved for identifies type of service running  next page 9

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 One of the biggest vulnerabilities of NetBIOS system -- NetBIOS Null session ◦ Is unauthenticated connection to a Windows computer  Does not use logon and passwords values  Attackers use enumeration tool to establish a null session ◦ to gather logon accounts, group membership, and file shares from target hosts 12

 NetBIOS NULL sessions are enabled by default in Windows NT and  Windows XP and 2003 will allow anonymous enumeration of shared network resources, but not accounts. 13

 For the most part if the appropriate ports are accessible a NULL session is possible. 14 PortProtocolDescription 135TCPLocation Service (RPC endpoint mapping) 135UDPLocation Service (RPC endpoint mapping) 137TCPNETBIOS Name Service 137UDPNETBIOS Name Service 138TCPNETBIOS Datagram Service 138UDPNETBIOS Datagram Service 139TCPNETBIOS Session Service 139UDPNETBIOS Session Service 445TCPSMB/CIFS

 Use IP address obtained when port scanning to perform a NetBIOS enumeration  NetBIOS Enumeration Tools ◦ Nbtstat ◦ Net view ◦ Net use ◦ NetScanTools Pro ◦ DumpSec ◦ Hyena ◦ NessusWX ◦ Enum ◦ Hunt 15

 Nbtstat command ◦ Powerful enumeration tool included with the Microsoft OS ◦ Displays NetBIOS table ◦ E.g., Nbstat –a salesrep 16

 Net view command ◦ Shows whether there are any shared resources on a network host  E.g., net view \\

 Net use command ◦ Used to connect to a computer with shared folders or files ◦ view the information about current computer connections. ◦ also can controls persistent network connections.  E.g., To assign the disk-drive device name E: to the Letters shared directory on the \\Fin server, type: net use e: \\fin\letters 18

 NetScanTools Pro produces a graphical view of NetBIOS running on a network ◦ Enumerates any shares running on the computer ◦ Verifies whether access is available for shared resource using its Universal Naming Convention (UNC) name ◦ Example: figure 6-10, 6-11  the \\SALEsMGR\SharedDocs comment entry is blank. to see whether access is available, an attacker enters the UNC \\SALEsMGR\SharedDocs in the Run dialog ox in Windows\\SALEsMGR\SharedDocs 19

 DumpSec in/download.pl?DumpAcl  Produced by Foundstone, Inc.  Allows user to connect to a server and “dump” the following information ◦ Permissions for shares ◦ Permissions for printers ◦ Permissions for the Registry ◦ Users in column or table format ◦ Policies and rights ◦ Services 20

 Hyena is GUI product for managing and securing Microsoft OSs ◦ Shows shares and user logon names for Windows servers and domain controllers ◦ Displays graphical representation of:  Microsoft Terminal Services  Microsoft Windows Network  Web Client Network  Find User/Group 21

 NessusWX allows enumeration of different OSs on a large network  Running NessusWX 1.Nessus server is up and running 2.Open the NessusWX client application 3.To connect your NessusWX client with the Nessus server 1.Click Communications, Connect from the menu on the session window 2.Enter server’s name 3.Log on the Nessus server 22

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Enum /Windows/enum_readme.cfm /Windows/enum_readme.cfm  one of the best tools for exploiting the NULL session vulnerability  allowing you to exploits every aspect of this flaw. ◦ the ability to enumerate users, ◦ and then try to brute force the password using a supplied password list. 25

Hunt ools/hunt.zip ools/hunt.zip  Part of the NT Forensic Toolkit from Foundstone,  this tool makes it very easy to enumerate users and shares from a vulnerable windows host, and is the most accurate 26

 Nessus identifies ◦ NetBIOS names in use ◦ Shared resources ◦ Password information 27

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 Nessus also identifies: ◦ OS and service pack ◦ OS vulnerabilities ◦ Firewall vulnerabilities 31

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 Introduction to Enumeration  Enumerate Microsoft OS  Enumerate *NIX OS 35

 variations of Unix ◦ Solaris ◦ SunOS ◦ HP-UX ◦ Linux ◦ Ultrix ◦ AIX ◦ BSD UNIX ◦ FreeBSD ◦ OpenBSD 36

 Finger utility ◦ Is the most popular tool for security testers ◦ Finds out who is logged in to a *NIX system ◦ Determine owner of any process  Nessus can also be used for *NIX enumeration 37

 E.g., # finger -b -p james display the following information about the user james. Login name, Computer Hope on since Feb 11 23:37:16 on pts/7 from domain.computerhope.com 28 seconds Idle Time Unread mail since Mon Feb 12 00:22: