ECCouncil Updated 312-50v13 Exam Questions and Answers by inaaya

After the attacker completes preparations, subsequent step is an effort to realize an edge within the target’s environment. a particularly common entry tactic is that the use of spearphishing emails containing an internet link or attachment. Email links usually cause sites where the target’s browser and related software are subjected to varied exploit techniques or where the APT actors plan to social engineer information from the victim which will be used later. If a successful exploit takes place, it installs an initial malware payload on the victim’s computer. Figure 2 illustrates an example of a spearphishing email that contains an attachment. Attachments are usually executable malware, a zipper or other archive containing malware, or a malicious Office or Adobe PDF (Portable Document Format) document that exploits vulnerabilities within the victim’s applications to ultimately execute malware on the victim’s computer. Once the user has opened a malicious file using vulnerable software, malware is executing on the target system. These phishing emails are often very convincing and difficult to differentiate from legitimate email messages. Tactics to extend their believability include modifying legitimate documents from or associated with the organization. Documents are sometimes stolen from the organization or their collaborators during previous exploitation operations. Actors modify the documents by adding exploits and malicious code then send them to the victims. Phishing emails are commonly sent through previously compromised email servers, email accounts at organizations associated with the target or public email services. Emails also can be sent through mail relays with modified email headers to form the messages appear to possess originated from legitimate sources. Exploitation of vulnerabilities on public-facing servers is another favorite technique of some APT groups. Though this will be accomplished using exploits for known vulnerabilities, 0-days are often developed or purchased to be used in intrusions as required .

Gaining an edge within the target environment is that the primary goal of the initial intrusion. Once a system is exploited, the attacker usually places malware on the compromised system and uses it as a jump point or proxy for further actions. Malware placed during the initial intrusion phase is usually an easy downloader, basic Remote Access Trojan or an easy shell. Figure 3 illustrates a newly infected system initiating an outbound connection to notify the APT actor that the initial intrusion attempt was successful which it’s able to accept commands.

ARP (Address Resolution Protocol) spoofing/poisoning is a common attack in which an attacker sends falsified ARP messages to associate their MAC address with the IP address of another host. To defend against ARP spoofing:

A. Port Security: Limits the number of MAC addresses per port; prevents MAC flooding and spoofing.

B. ARPwatch: Monitors ARP traffic and alerts on unusual changes.

D. Static ARP Entries: Prevent ARP responses from overwriting MAC-IP mappings, effective in small networks.

From CEH v13 Official Courseware:

Module 8: Sniffing

Module 11: Session Hijacking

Module 20: Network Security

Incorrect Options:

C: Firewalls operate at Layer 3+; ARP is a Layer 2 protocol, so firewalls don’t prevent ARP spoofing.

E: Static IP addresses do not prevent ARP poisoning.

https://en.wikipedia.org/wiki/Meet-in-the-middle_attack

The meet-in-the-middle attack (MITM), a known plaintext attack, is a generic space–time tradeoff cryptographic attack against encryption schemes that rely on performing multiple encryption operations in sequence. The MITM attack is the primary reason why Double DES is not used and why a Triple DES key (168-bit) can be bruteforced by an attacker with 256 space and 2112 operations.

The intruder has to know some parts of plaintext and their ciphertexts. Using meet-in-the-middle attacks it is possible to break ciphers, which have two or more secret keys for multiple encryption using the same algorithm. For example, the 3DES cipher works in this way. Meet-in-the-middle attack was first presented by Diffie and Hellman for cryptanalysis of DES algorithm.

In CEH v13 Module 06: Malware Threats, code emulation is defined as a technique used by modern antivirus software where a virtual CPU and memory are created to safely execute and analyze malware in a sandboxed environment.

This allows the detection engine to observe runtime behavior of suspicious code without risking the actual system.

It’s more effective than signature-based detection for catching polymorphic and obfuscated malware.