CREST CPSA Exam

CREST CPSA Exam Questions and Answers NEW!! Name Four TCP head flags - answer--ACK, FIN, SYN, URG, PSH, RST Which layer does HTTP protocl reside in the OSI model. - answer--Layer 7, Application. Which layer does Ethernet reside in the OSI model. - answer--Layer 2, Data link. Which Layer does IPv4 & IPv6 reside in TCP/IP model. - answer--Layer 4, transport. RFC 1918 addresses - answer--10.0.0.0 - 10.255.255.255 (10/8 prefix) 172.16.0.0 - 172.31.255.255 (172.16/12 prefix) 192.168.0.0 - 192.168.255.255 (192.168/16 prefix) Name the well know, registered and dynamic port ranges. - answer--Well Known(0- 1023), Registed(1024-49,151) & Dynamic(49,152-65,535) Name all OSI layers - answer--Application, Presentation, Session, Transport, Network, Data Link, Physical. Name all TCP/IP layers - answer--Application, Transport, internet, Network Access. What is an ephemeral port? - answer--An ephemeral port is a short-lived transport protocol port for Internet Protocol (IP) communications. Can be used by both TCP & UDP. What does IANA stand for? - answer--Internet Assigned Numbers Authority Name 10 common ports and there protocols. - answer--FTP21, SSH22, DHCP67(C), DHCP68(S), NTP123, MYSQL3306, RDP3389, HTTP80, HTTPS443, SMB445, KERBEROS88, CHARGEN19(UDP), DNS53, TACAS49, WHOIS43, MSSQL1433, HIDDEN MSSQL2433. Name five network types. - answer--LAN, WAN, MAN, VLAN, WLAN, PAN. Name five network topologies - answer--Mesh, Ring, star, Tree, Bus. Name five common ethernet and FDDI cable types. - answer--100Base5, 10Base2, 10BaseT, 100Base-FL, 1000Base-T. What is WIFI the alias for? - answer--IEEE 802.11 What does VLAN stand for? - answer--Virtual Local Area Network How does VLAN work? - answer--Virtual Local Area Networks (VLANs) separate an existing physical network into multiple logical networks. Thus, each VLAN creates its own broadcast domain. Communication between two VLANs can only occur through a router that is connected to both. Name five common ICMP types. - answer--8-echo, 0-echo reply, 30-trace route, 5- redirect, 3-destination unreachable, 11, time execeed. What does ICMP stand for? - answer--Internet Control Message Protocol What does TTL stand for? - answer--Time to Live What is TTL? - answer--TTL is a hop count system, and each router decreases the TTL by 1. Upon reaching 0, the packet is dropped. This way you don't have packets not reaching their destination and clogging the network. OS TLL numbers? - answer--128 Windows, 64 linux, 255 solaris(kapp) What is Traceroute - answer--Traceroute is when you send a packet with a TTL value of 1 once it reaches the first router it will die sending a ICMP message to sender, at which point the sender can send another one with a value of 2 to see how far it will go. By doing this we can see how many hops it will take to reach our target. (A good way of enumeration of a network, when in a black box pen-test.) What is ping sweep? - answer--Ping sweep is just a technique that can be used to find out which hosts are alive in a network or large number of IP addresses. Name Five Namp Flags. - answer--(TCP SYN scan, -sS) (Null Scan, -sN) (Ping Scan, -sP) (Ack Scan, -sA) (OS dect, -O) What are the three firewall states? - answer--Open, Filtered Dropped Blocked, Closed not listening. What is TCP window size? - answer--Window size a method of controlling the flow of packets between two computers or network hosts. Decieded in the tcp three way handshake. What is encoding? - answer--Encoding transforms data into another format using a scheme that is publicly available so that it can easily be reversed. What is encryption? - answer--scrambles information into an alternative form that requires a key or password to decrypt the information back into its orginial form. What is hashing - answer--Hashing serves the purpose of ensuring integrity, i.e. making it so that if something is changed you can know that it's changed. What is obfuscation? - answer--The purpose of obfuscation is to make something harder to understand, usually for the purposes of making it more difficult to attack or to copy. What is symmetric encryption? - answer--An encryption method in which the same key is used to encrypt and decrypt the data. What is asymmetric encryption? - answer--An encryption method in which two keys (one private, one public) are used to encrypt and decrypt a message. Vunerable hashing algorithms - answer--MD5, Sha-1, NTLM, LanMan. Eny Symmertric algorithms. - answer-- DES 3DES (or Triple DES) RC4 RC5 AES (aka Rijndael) Blowfish Serpent Twofish CAST5 IDEA Eny Asymmertric algorithms. - answer-- Elliptic curve RSA Diffie-Hellman DSA Key serialization ELGAMAL What is a hash collision? - answer--A Hash Collision Attack is an attempt to find two input strings of a hash function that produce the same hash result. Because hash functions have infinite input length and a predefined output length, there is inevitably going to be the possibility of two different inputs that produce the same output hash. What is Ipsec. - answer--Internet Protocol Security (IPsec) is a secure network protocol suite that authenticates and encrypts the packets of data sent over an Internet Protocol network.