Chapter 11 - 02 - Understand Wireless Network Encryption Mechanisms - 01_ocred_fax_ocred.pdf

Certified Cybersecurity Technician Exam 212-82 Wireless Network Security Module Flow Discuss Different Types...

Certified Cybersecurity Technician Exam 212-82 Wireless Network Security Module Flow Discuss Different Types Wireless Network Understand Wireless of Wireless Network Encryption Mechanisms Authentication Methods Discuss and Implement Understand Wireless Wireless Network Network Fundamentals Security Measures Understand Wireless Network Encryption Mechanisms The objective of this section is to explain the various encryption mechanisms used in wireless networks, such as WEP encryption, wireless fidelity (Wi-Fi) protected access (WPA) Encryption, Wi-Fi protected access 2 (WPA2) encryption, Wi-Fi protected access 3 (WPA3) encryption. This section also describes the limitations of these encryption mechanisms. Module 11 Page 1427 Certified Cybersecurity Technician Copyright © by EC-Council All Rights Reserved. Reproduction is Strictly Prohibited. Certified Cybersecurity Technician Exam 212-82 Wireless Network Security Types of Wireless Encryption IEEE amendment that specifies security mechanisms An |IEEE for 802.11 wireless networks An encryption algorithm for IEEE 802.11 wireless networks Supports multiple authentication methods, such as token cards, Kerberos, and certificates A proprietary version of EAP developed by Cisco An advanced wireless encryption protocol using TKIP and MIC to provide stronger encryption and authentication A security protocol used in WPA as a replacement for WEP - v v Copyright ©© by EC L All All Rights Reserved. Reserved. Reproduction Reproduction Is Strictly Strictly Prohibited. J Types of Wireless Encryption (Cont’d) An upgrade to WPA using AES and CCMP for wireless data encryption A symmetric-key encryption, used in WPA2 as a replacement for TKIP An encryption protocol used in WPA2 for stronger encryption and authentication Integrates EAP standards with WPA2 encryption A centralized authentication and authorization management system system A protocol that encapsulates the EAP within an encrypted and authenticated transport layer security (TLS) tunnel A third-generation Wi-Fi security protocol that uses GCMP-256 for encryption and HMAC-SHA-384 for authentication Copyright © by EC Copyright © by E ILL AllAll Rights Rights Reserved. Reproduction Reserved. Reproduction ss Strictly Strictly Prohibited. Prohibited. Types of Wireless Encryption There are several types of wireless encryption algorithms that can secure a wireless network. Each wireless encryption algorithm has advantages and disadvantages. = 802.11i: It is an IEEE amendment that specifies security mechanisms for 802.11 wireless networks. Module 11 Page 1428 Certified Cybersecurity Technician Copyright © by EC-Council All Rights Reserved. Reproduction is Strictly Prohibited. Certified Cybersecurity Technician Exam 212-82 Wireless Network Security = WEP: WEP is an encryption algorithm for IEEE 802.11 wireless networks. It is an old wireless security standard and can be cracked easily. = EAP: The Extensible Authentication Protocol (EAP) supports multiple authentication methods, such as token cards, Kerberos, and certificates. = LEAP: Lightweight EAP (LEAP) is a proprietary version of EAP developed by Cisco. = WHPA: It is an advanced wireless encryption protocol using TKIP and Message Integrity Check (MIC) to provide strong encryption and authentication. It uses a 48-bit initialization vector (1V), 32-bit cyclic redundancy check (CRC), and TKIP encryption for wireless security. = TKIP: It is a security protocol used in WPA as a replacement for WEP. = WPA2: It is an upgrade to WPA using AES and the Counter Mode Cipher Block Chaining Message Authentication Code Protocol (CCMP) for wireless data encryption. = AES: It is a symmetric-key encryption used in WPA2 as a replacement for TKIP. = CCMP: It is an encryption protocol used in WPA2 for strong encryption and authentication. = WPA2 Enterprise: It integrates EAP standards with WPA2 encryption. = RADIUS: It is a centralized authentication and authorization management system. = PEAP: It is a protocol that encapsulates the EAP within an encrypted and authenticated Transport Layer Security (TLS) tunnel. = WHPA3: It is a third-generation Wi-Fi security protocol that provides new features for personal and enterprise usage. It uses Galois/Counter Mode-256 (GCMP-256) for encryption and the 384-bit hash message authentication code with the Secure Hash Algorithm (HMAC-SHA-384) for authentication. Module 11 Page 1429 Certified Cybersecurity Technician Copyright © by EG-Council All Rights Reserved. Reproduction is Strictly Prohibited. Certified Cybersecurity Technician Exam 212-82 Wireless Network Security Wired Equivalent Privacy (WEP) Encryption WEP is a security protocol defined by the 802.11b standard; it was designed to provide a wireless LAN with a level of i comparable to that of a wired LAN WEP it initiali ) to form stream cipher RC4 for confidentiality and the CRC-32 checksum for integrity of wireless transmissions It has significant vulnerabilities and design flaws and v WEP Key Store prisnsressdireeseiieeieiennieenen,. (K1, K2, K3, K4) [ I : CRC-32 : Data Icv : Checksum T —— A : i H ’P How WEP Works : XOR Agorithm €3 : et B T — N : [ WEP Key I v ] '>r Keystream [ v IPAD KID Ciphertext J.,....... : 3 aenene AL. ; $ i WEP-encrypted Packet (Frame body of MAC Frame) Wired Equivalent Privacy (WEP) Encryption WEP was an early attempt to protect wireless networks from security breaches, but as technology improved, it became evident that information encrypted with WEP is vulnerable to attack. We discuss WEP in detail here. What is WEP Encryption? WEP is a component of the IEEE 802.11 WLAN standards. Its primary purpose is to ensure data confidentiality on wireless networks at a level equivalent to that of wired LANs, which can use physical security to stop unauthorized access to a network. In @ WLAN, a user or an attacker can access the network without physically connecting to the LAN. Therefore, WEP utilizes an encryption mechanism at the data link layer for minimizing unauthorized access to the WLAN. This is accomplished by encrypting data with the symmetric Rivest Cipher 4 (RC4) encryption algorithm, which is a cryptographic mechanism used to defend against threats. Role of WEP in Wireless Communication = WEP protects against eavesdropping on wireless communications. = |t attempts to prevent unauthorized access to a wireless network. = |t depends on a secret key shared by a mobile station and an AP. This key encrypts packets before transmission. Performing an integrity check ensures that packets are not altered during transmission. 802.11 WEP encrypts only the data between network clients. Module 11 Page 1430 Certified Cybersecurity Technician Copyright © by EG-Council All Rights Reserved. Reproduction is Strictly Prohibited. Certified Cybersecurity Technician Exam 212-82 Wireless Network Security Main Advantages of WEP = Confidentiality: It prevents link-layer eavesdropping. = Access Control: It determines who may access data. = Data Integrity: It protects the change of data by a third party. = Efficiency Key Points WEP was developed without any academic or public review. In particular, it was not reviewed by cryptologists during development. Therefore, it has significant vulnerabilities and design flaws. WEP is a stream cipher that uses RC4 to produce a stream of bytes that are XORed with plaintext. The length of the WEP and secret key are as follows: = 64-bit WEP uses a 40-bit key = 128-bit WEP uses a 104-bit key = 256-bit WEP uses 232-bit key Flaws of WEP The following basic flaws undermine WEP’s ability to protect against a serious attack. * No defined method for encryption key distribution: o Pre-shared keys (PSKs) are set once at installation and are rarely (if ever) changed. o Itis easy to recover the number of plaintext messages encrypted with the same key. = RC4 was designed to be used in a more randomized environment than that utilized by WEP: o Asthe PSK is rarely changed, the same key is used repeatedly. o An attacker monitors the traffic and finds different ways to work with the plaintext message. o With knowledge of the ciphertext and plaintext, an attacker can compute the key. = Attackers analyze the traffic from passive data captures and crack WEP keys with the help of tools such as AirSnort and WEPCrack. = Key scheduling algorithms are also vulnerable to attack. How WEP Works = (CRC-32 checksum is used to calculate a 32-bit integrity check value (ICV) for the data, which, in turn, is added to the data frame. = A 24-bit arbitrary number known as the initialization vector (IV) is added to the WEP key; the WEP key and IV are together called the WEP seed. Module 11 Page 1431 Certified Cybersecurity Technician Copyright © by EG-Council All Rights Reserved. Reproduction is Strictly Prohibited. Certified Cybersecurity Technician Exam 212-82 Wireless Network Security = The WEP seed is used as the input to the RC4 algorithm to generate a keystream, which is bit-wise XORed with a combination of the data and ICV to produce the encrypted data. = The IV field (IV + PAD + KID) is added to the ciphertext to generate a MAC frame. p. RN Y WEP Key Store RSLIIIITINS. TT YT YT TT TP TP rras. (K1, K2, K3, K4) : CRC-32 \_ ) : Data icv. Checksum S >IEE 2 e $ - § : WEP Seed XOR Algorithm ?...................................................................... L L TTTPPPPPPPRPT PO [ WEP Key I v ] IILELILLED > { Keystream [ I PAD I KID I Ciphertext ] : WEP-encrvpted Packet (Frame body of N e e En s e NI esesasssNNrseees s aNs NsssssssseNNRIIRRERRRRRIREES < MAC Frame) Figure 11.7: Operational flow of WEP Module 11 Page 1432 Certified Cybersecurity Technician Copyright © by EG-Council All Rights Reserved. Reproduction is Strictly Prohibited.