Destination unreachable administratively prohibited messages can inform the hacker to what?
A. That a circuit level proxy has been installed and is filtering traffic
B. That his/her scans are being blocked by a honeypot or jail
C. That the packets are being malformed by the scanning software
D. That a router or other packet-filtering device is blocking traffic
E. That the network is functioning normally
Destination unreachable administratively prohibited messages are a good way to discover that a router or other low-level packet device is filtering traffic. Analysis of the ICMP message will reveal the IP address of the blocking device and the filtered port. This further adds the to the network map and information being discovered about the network and hosts.
Which of the following Nmap commands would be used to perform a stack fingerprinting?
A. Nmap -O -p80
B. Nmap -hU -Q
C. Nmap -sT -p
D. Nmap -u -o -w2
E. Nmap -sS -0p target
This option activates remote host identification via TCP/IP fingerprinting. In other words,it uses a bunch of techniques to detect subtlety in the underlying operating system network stack of the computers you are scanning. It uses this information to create a “fingerprint” which it compares with its database of known OS fingerprints (the nmap-os-fingerprints file. to decide what type of system you are scanning.
(Note: the student is being tested on concepts learnt during passive OS fingerprinting, basic TCP/IP connection concepts and the ability to read packet signatures from a sniff dump.)
Snort has been used to capture packets on the network. On studying the packets, the penetration tester finds it to be abnormal. If you were the penetration tester, why would you find this abnormal?
What is odd about this attack? Choose the best answer.
A. This is not a spoofed packet as the IP stack has increasing numbers for the three flags.
B. This is back orifice activity as the scan comes form port 31337.
C. The attacker wants to avoid creating a sub-carries connection that is not normally valid.
D. These packets were crafted by a tool,they were not created by a standard IP stack.
Port 31337 is normally used by Back Orifice. Note that 31337 is hackers spelling of neliteo,meaning nelite hackerso.
Which type of Nmap scan is the most reliable, but also the most visible, and likely to be picked up by and IDS?
A. SYN scan
B. ACK scan
C. RST scan
D. Connect scan
E. FIN scan
The TCP full connect (-sT) scan is the most reliable.
Name two software tools used for OS guessing? (Choose two.
Nmap and Queso are the two best-known OS guessing programs. OS guessing software has the ability to look at peculiarities in the way that each vendor implements the RFC’s. These differences are compared with its database of known OS fingerprints. Then a best guess of the OS is provided to the user.
Sandra is the security administrator of XYZ.com. One day she notices that the XYZ.com Oracle database server has been compromised and customer information along with financial data has been stolen. The financial loss will be estimated in millions of dollars if the database gets into the hands of competitors. Sandra wants to report this crime to the law enforcement agencies immediately.
Which organization coordinates computer crime investigations throughout the United States?
While reviewing the result of scanning run against a target network you come across the following:
Which among the following can be used to get this output?
A. A Bo2k system query.
B. nmap protocol scan
C. A sniffer
D. An SNMP walk
SNMP lets you “read” information from a device. You make a query of the server (generally known as the “agent”). The agent gathers the information from the host system and returns the answer to your SNMP client. It’s like having a single interface for all your informative Unix commands. Output like system.sysContact.0 is called a MIB.
You are manually conducting Idle Scanning using Hping2. During your scanning you notice that almost every query increments the IPID regardless of the port being queried. One or two of the queries cause the IPID to increment by more than one value. Why do you think this occurs?
A. The zombie you are using is not truly idle.
B. A stateful inspection firewall is resetting your queries.
C. Hping2 cannot be used for idle scanning.
D. These ports are actually open on the target system.
If the IPID is incremented by more than the normal increment for this type of system it means that the system is interacting with some other system beside yours and has sent packets to an unknown host between the packets destined for you.
While performing ping scans into a target network you get a frantic call from the organizationos security team. They report that they are under a denial of service attack. When you stop your scan, the smurf attack event stops showing up on the organizationos IDS monitor. How can you modify your scan to prevent triggering this event in the IDS?
A. Scan more slowly.
B. Do not scan the broadcast IP.
C. Spoof the source IP address.
D. Only scan the Windows systems.
Scanning the broadcast address makes the scan target all IP addresses on that subnet at the same time.
Neil notices that a single address is generating traffic from its port 500 to port 500 of several other machines on the network. This scan is eating up most of the network bandwidth and Neil is concerned. As a security professional, what would you infer from this scan?
A. It is a network fault and the originating machine is in a network loop
B. It is a worm that is malfunctioning or hardcoded to scan on port 500
C. The attacker is trying to detect machines on the network which have SSL enabled
D. The attacker is trying to determine the type of VPN implementation and checking for IPSec
Port 500 is used by IKE (Internet Key Exchange). This is typically used for IPSEC-based VPN software,such as Freeswan,PGPnet,and various vendors of in-a-box VPN solutions such as Cisco. IKE is used to set up the session keys. The actual session is usually sent with ESP (Encapsulated Security Payload) packets,IP protocol 50 (but some in-a-box VPN’s such as Cisco are capable of negotiating to send the encrypted tunnel over a UDP channel,which is useful for use across firewalls that block IP protocols other than TCP or UDP).