An audacious attacker is targeting a web server you oversee. He intends to perform a Slow HTTP POST attack, by manipulating 'a' HTTP connection. Each connection sends a byte of data every 'b' second, effectively holding up the connections for an extended period. Your server is designed to manage 'm' connections per second, but any connections exceeding this number tend to overwhelm the system. Given 'a=100' and variable 'm', along with the attacker's intention of maximizing the attack duration 'D=a*b', consider the following scenarios. Which is most likely to result in the longest duration of server unavailability?
Answer : B
A Slow HTTP POST attack is a type of denial-of-service (DoS) attack that exploits the way web servers handle HTTP requests. The attacker sends a legitimate HTTP POST header to the web server, specifying a large amount of data to be sent in the request body. However, the attacker then sends the data very slowly, keeping the connection open and occupying the server's resources. The attacker can launch multiple such connections, exceeding the server's capacity to handle concurrent requests and preventing legitimate users from accessing the web server.
The attack duration D is given by the formula D = a * b, where a is the number of connections and b is the hold-up time per connection. The attacker intends to maximize D by manipulating a and b. The server can manage m connections per second, but any connections exceeding m will overwhelm the system. Therefore, the scenario that is most likely to result in the longest duration of server unavailability is the one where a > m and b is the largest. Among the four options, this is the case for option B, where a = 100, m = 90, and b = 15. In this scenario, D = 100 * 15 = 1500 seconds, which is the longest among the four options. Option A has a larger b, but a < m, so the server can handle the connections without being overwhelmed. Option C has a > m, but a smaller b, so the attack duration is shorter. Option D has a > m, but a smaller b and a smaller difference between a and m, so the attack duration is also shorter. Reference:
What is a Slow POST Attack & How to Prevent One? (Guide)
Mitigate Slow HTTP GET/POST Vulnerabilities in the Apache HTTP Server - Acunetix
What is a Slow Post DDoS Attack? | NETSCOUT
During a red team engagement, an ethical hacker is tasked with testing the security measures of an organization's wireless network. The hacker needs to select an appropriate tool to carry out a session hijacking attack. Which of the following tools should the hacker use to effectively perform session hijacking and subsequent security analysis, given that the target wireless network has the Wi-Fi Protected Access-preshared key (WPA-PSK) security protocol in place?
Answer : D
Therefore, bettercap is an appropriate tool to carry out a session hijacking attack on a wireless network that uses the WPA-PSK security protocol.
As a security analyst for Sky Secure Inc., you are working with a client that uses a multi-cloud strategy, utilizing services from several cloud providers. The client wants to implement a system that will provide unified security management across all their cloud platforms. They need a solution that allows them to consistently enforce security policies, identify and respond to threats, and maintain visibility of all their cloud resources. Which of the following should you recommend as the best solution?
Answer : C
A Cloud Access Security Broker (CASB) is a security policy enforcement point, either on-premises or in the cloud, that administers an organization's enterprise security policies when users attempt to access its cloud-based resources. A CASB can provide unified security management across multiple cloud platforms, as it can monitor cloud activity, enforce security policies, identify and respond to threats, and maintain visibility of all cloud resources. A CASB can also integrate with other security tools, such as data loss prevention (DLP), encryption, malware detection, and identity and access management (IAM), to enhance the security posture of the organization.
The other options are not as effective or feasible as using a CASB. Using a hardware-based firewall to secure all cloud resources may not be compatible with the dynamic and scalable nature of the cloud, as it may introduce latency, complexity, and cost. Implementing separate security management tools for each cloud platform may create inconsistency, inefficiency, and confusion, as each tool may have different features, interfaces, and configurations. Relying on the built-in security features of each cloud platform may not be sufficient or comprehensive, as each platform may have different levels of security, compliance, and functionality.Reference:
What Is a Cloud Access Security Broker (CASB)? | Microsoft
What Is a CASB? - Cloud Access Security Broker - Cisco
What is a Cloud Access Security Broker (CASB)?
A network security analyst, while conducting penetration testing, is aiming to identify a service account password using the Kerberos authentication protocol. They have a valid user authentication ticket (TGT) and decided to carry out a Kerberoasting attack. In the scenario described, which of the following steps should the analyst take next?
Answer : D
A Kerberoasting attack is a technique that exploits the weak encryption of Kerberos service tickets to obtain the password hashes of service accounts that have a Service Principal Name (SPN) associated with them. The attacker can then crack the hashes offline and use the plaintext passwords to impersonate the service accounts and access network resources.
A Kerberoasting attack follows these steps1:
The attacker impersonates a legitimate Active Directory user and authenticates to the Key Distribution Center (KDC) in the Active Directory environment. They then request a Ticket Granting Ticket (TGT) from the KDC to access network resources. The KDC complies because the attacker is impersonating a legitimate user.
The attacker enumerates the service accounts that have an SPN using tools like GetUserSPNs.py or PowerView. They then request a service ticket for each SPN from the KDC using their TGT. The KDC grants the service tickets, which are encrypted with the password hashes of the service accounts.
Once the attacker obtains the plaintext passwords of the service accounts, they can use them to authenticate as the service accounts and access the network resources that they are authorized to.
Therefore, the next step that the analyst should take after obtaining a valid TGT is to request a service ticket for the SPN of the target service account. This will allow them to capture the service ticket and extract the password hash of the service account.
How to Perform Kerberoasting Attacks: The Ultimate Guide - StationX
A security analyst is preparing to analyze a potentially malicious program believed to have infiltrated an organization's network. To ensure the safety and integrity of the production environment, the analyst decided to use a sheep dip computer for the analysis. Before initiating the analysis, what key step should the analyst
take?
Answer : B
A sheep dip computer is a dedicated device that is used to test inbound files or physical media for viruses, malware, or other harmful content, before they are allowed to be used with other computers. The term sheep dip comes from a method of preventing the spread of parasites in a flock of sheep by dipping the new animals that farmers are adding to the flock in a trough of pesticide. A sheep dip computer is isolated from the organization's network and has port monitors, file monitors, network monitors, and antivirus software installed. Before initiating the analysis of a potentially malicious program, the analyst should store the program on an external medium, such as a CD-ROM, and then insert it into the sheep dip computer. This way, the analyst can prevent the program from infecting other devices or spreading over the network, and can safely analyze its behavior and characteristics.
The other options are not correct steps to take before initiating the analysis. Running the potentially malicious program on the sheep dip computer may cause irreversible damage to the device or compromise its security. Connecting the sheep dip computer to the organization's internal network may expose the network to the risk of infection or attack. Installing the potentially malicious program on the sheep dip computer may not be possible or advisable, as the program may require certain dependencies or permissions that the sheep dip computer does not have or allow. Reference:
What Does 'Sheep Dip' Mean in Cyber Security?
While performing a security audit of a web application, an ethical hacker discovers a potential vulnerability.
The application responds to logically incorrect queries with detailed error messages that divulge the underlying database's structure. The ethical hacker decides to exploit this vulnerability further. Which type of SQL Injection attack is the ethical hacker likely to use?
Answer : D
Error-based SQL Injection is a type of in-band SQL Injection attack that relies on error messages thrown by the database server to obtain information about the structure of the database. In some cases, error-based SQL injection alone is enough for an attacker to enumerate an entire database.
The ethical hacker is likely to use this type of SQL Injection attack because the application responds to logically incorrect queries with detailed error messages that divulge the underlying database's structure. This means that the attacker can craft malicious SQL queries that trigger errors and reveal information such as table names, column names, data types, etc. The attacker can then use this information to construct more complex queries that extract data from the database.
For example, if the application uses the following query to display the username of a user based on the user ID:
SELECT username FROM users WHERE id = '$id'
The attacker can inject a single quote at the end of the user ID parameter to cause a syntax error:
SELECT username FROM users WHERE id = '1'
The application might display an error message like this:
You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''1'' at line 1
This error message reveals that the database server is MySQL and that the user ID parameter is enclosed in single quotes. The attacker can then use other techniques such as UNION, subqueries, or conditional statements to manipulate the query and retrieve data from other tables or columns.
[CEHv12 Module 05: Sniffing]
In a large organization, a network security analyst discovered a series of packet captures that seem unusual.
The network operates on a switched Ethernet environment. The security team suspects that an attacker might
be using a sniffer tool. Which technique could the attacker be using to successfully carry out this attack,
considering the switched nature of the network?
Answer : B
A sniffer tool is a software or hardware device that can capture and analyze network traffic. In a switched Ethernet environment, where each port on a switch is connected to a single device, a sniffer tool can only see the traffic that is destined for or originated from the device it is attached to. However, an attacker can use various techniques to overcome this limitation and sniff the traffic of other devices on the same network. One of these techniques is MAC flooding, which exploits the finite memory of the switch's MAC address table. The attacker sends a large number of frames with different source MAC addresses to the switch, which fills up the MAC address table and causes the switch to enter a fail-open mode, where it broadcasts all incoming frames to all ports, regardless of the destination MAC address. This way, the attacker can see all the traffic on the network and capture it with a sniffer tool.
The other options are less likely or less effective techniques for sniffing a switched Ethernet network. Compromising physical security to plug into the network directly may allow the attacker to sniff the traffic of the device they are connected to, but not the traffic of other devices on the network. Using a Trojan horse with in-built sniffing capability may allow the attacker to sniff the traffic of the infected device, but not the traffic of other devices on the network, unless the Trojan horse also performs MAC flooding or other techniques to bypass the switch. Using passive sniffing, which involves listening to the network traffic without sending any packets, may provide significant stealth advantages, but it does not help the attacker to see the traffic of other devices on the network, unless the switch is already in fail-open mode or the attacker uses other techniques to induce it. Reference:
Sniffing: A Beginners Guide In 4 Important Points
How can I run a packet sniffer on a Router or Switch
Detection of Sniffers in an Ethernet Network