312-50v13 Premium Exam Questions

aLTEr attacks are usually performed on LTE devices Attacker installs a virtual (fake) communication tower between two authentic endpoints intending to mislead the victim This virtual tower is used to interrupt the data transmission between the user and real tower attempting to hijack the active session.

The new aLTEr attack can be used against nearly all LTE connected endpoints by intercepting traffic and redirecting it to malicious websites together with a particular approach for Apple iOS devices.

This attack works by taking advantage of a style flaw among the LTE network — the information link layer (aka: layer-2) of the LTE network is encrypted with AES-CTR however it’s not integrity-protected, that is why an offender will modify the payload.

As a result, the offender is acting a classic man-in-the-middle wherever they’re movement as a cell tower to the victim.

Gathering Wordlist from the Target Website An attacker uses the CeWL tool to gather a list of words from the target website and perform a brute-force attack on the email addresses gathered earlier. # Cewl (P.200/184)

A web application firewall (WAF) is a specific form of application firewall that filters, monitors, and blocks HTTP traffic to and from a web service. By inspecting HTTP traffic, it can prevent attacks exploiting a web application's known vulnerabilities, such as SQL injection, cross-site scripting (XSS), file inclusion, and improper system configuration.

In CEH v13 Module 03: Scanning Networks, the behavior of firewalls in response to ACK scans is described in detail, especially regarding stateful vs. stateless firewalls.

An ACK scan (nmap -sA) is primarily used for firewall rule analysis. Here’s how it works:

When you send a TCP ACK segment:

If the port is closed and no firewall is present, the target should respond with a TCP RST packet.

If a stateless (non-stateful) firewall is used, it typically allows or blocks packets based only on rules about IP addresses, ports, and protocol type, without tracking session state.

If a stateful firewall is used, it keeps track of connection states. Therefore:

An unsolicited ACK packet (not part of any established session) will be silently dropped, because it doesn’t correspond to any active connection.

No RST is sent back because the firewall suppresses it, recognizing it as potentially malicious or out of context.

Therefore:

No RST response = packet was silently dropped.

Silent dropping of unsolicited ACK packets = Stateful Firewall Behavior.

Option Analysis:

A. There is no firewall in place

❌ Incorrect. If there were no firewall, an RST would be sent from the closed port.

B. This event does not tell you anything about the firewall

❌ Incorrect. The lack of a response is actually meaningful and implies stateful filtering behavior.

C. It is a stateful firewall

Correct. A stateful firewall inspects the packet, sees no valid session, and drops it silently.

D. It is a non-stateful firewall

❌ Incorrect. A non-stateful firewall would typically not inspect session state, and you'd still expect to see a response (likely an RST).

Reference from CEH v13 Study Guide and Courseware:

Module 03 – Scanning Networks, Section: Nmap Scanning Techniques → TCP ACK Scan

CEH Engage Labs – Network Scanning Phase: Firewall Rule Detection using ACK Scans