200-201 Exam Dumps - Cisco CyberOps Associate Questions and Answers

Email greylisting is an anti-spam technique used by mail transfer agents to reduce unsolicited and malicious email traffic. When an email is received from an unknown sender, the MTA temporarily rejects the message with a request for retransmission. Legitimate mail servers are configured to retry delivery after a short delay, while many spam and malicious servers do not.

By allowing emails from unknown senders temporarily after a retry, greylisting effectively filters out a large volume of automated spam without relying on content inspection or signatures. This makes it a lightweight and effective control in email security architectures.

Option A describes quarantining, which is different from greylisting. Option B refers to permanent blocking, which greylisting does not do. Option C relates to phishing detection rather than delivery control behavior.

Security monitoring documentation highlights greylisting as a behavior-based control that leverages standard SMTP retry mechanisms. Once a sender successfully retries, they are typically whitelisted for future deliveries.

Therefore, email greylisting works by temporarily delaying emails from unknown senders, making Option D the correct answer.

Deep packet inspection (DPI) is a sophisticated method of examining the content of data packets as they pass through a network checkpoint, including both the header and the data payload. DPI is typically performed at the application layer of the Open Systems Interconnection (OSI) model. This allows the inspection process to evaluate the actual content of the packets, not just the header information, enabling the identification of various types of threats and the enforcement of network policies1.

References := The explanation aligns with the information provided by Digital Guardian, which details how DPI works and at which layer it is applied1.

The exhibit shows a Stealthwatch dashboard displaying information on alarming hosts, alarms by type, and today’s alarms. On the left side under “Top Alarming Hosts,” there are five host IP addresses listed with their respective categories indicating different types of alerts including ‘Data Hoarding’ and ‘Exfiltration.’ In “Alarms by Type” section at center top part of image shows bar graphs representing various alarm types including ‘Crypto Violation’ with their respective counts. On right side under “Today’s Alarms,” there’s a table showing the details of each alarm such as the host IP, the alarm type, the severity, and the time. The potential threat identified in this dashboard is that there are two active data exfiltration alerts, one for host 10.201.3.149 and another for host 10.10.101.24. Data exfiltration is the unauthorized transfer of data from a compromised system to an external destination, such as a command and control server or a malicious actor. This can result in data loss, breach of confidentiality, and damage to the organization’s reputation and assets. References := Cisco Cybersecurity Operations Fundamentals - Module 7: Network and Host Forensics

The exhibit shows a network diagram with a switch, a router, and two hosts. The switch has a MAC address table that maps the MAC addresses of the connected devices to the corresponding ports. A MAC flooding attack is a type of attack that aims to overload the switch’s MAC address table by sending a large number of frames with spoofed source MAC addresses. This causes the switch to enter a fail-open mode, where it broadcasts all incoming frames to all ports, effectively turning it into a hub. This allows the attacker tosniff the traffic between the hosts and the router, or launch other attacks such as ARP spoofing or man-in-the-middle

An Nmap scan can provide detailed information about a network including the functionality and purpose of servers on that network as well as any services that are currently running on those servers. This information can be used by an attacker to identify potential vulnerabilities or targets for exploitation during a cyber attack. References := Cisco Cybersecurity Training

The engineer engaged with the service component by enabling “Audiosrv,” which is the Windows Audio Service responsible for managing audio for Windows-based programs. By setting it to auto-start, the engineer ensured that the service would run automatically upon system startup. Additionally, the engineer interacted with process and thread management by using the Task Manager to modify the behavior of the “Audiosrv” service.

The information is based on standard operating procedures for troubleshooting audio issues in Windows OS, which involves services and processes management.

After a breach has been discovered and the immediate threat has been addressed by identifying and removing the threat’s access, the next step according to the NIST SP 800-61 Incident Handling Guide is to recover from the threat. This involves restoring systems to normal operation, confirming that the systems are functioning normally, and applying patches or other remediation measures to prevent similar breaches in the future1.

References :=

Understanding NIST SP 800-61: The Computer Security Incident Handling Guide