The "ps" command is used to display information about the processes running on a system. The "-ef" option shows the full format listing, which includes the process ID, the user, the CPU and memory usage, the command name, and other details. This can help the engineer identify which processes are consuming the most resources and causing the degraded performance of the server. The other options are either invalid or irrelevant, as they do not provide the necessary information or perform the required action. References := Cisco Cybersecurity

The packet capture exhibit shows that the source IP address is 192.168.122.100 and it is sending a packet from source port 50272 to destination port 80 of destination IP address 81.179.179.69 using TCP protocol.
The TCP protocol is indicated by the Protocol field which has the value 6. The source and destination ports are indicated by the SrcPort and DstPort fields respectively. The source and destination IP addresses are indicated by the SrcAddr and DstAddr fields respectively. References := Cisco Cybersecurity Operations Fundamentals - Module 3: Network Data and Event Analysis

An SSL certificate enables the establishment of a secure connection between the client and the server using the TLS protocol. The client and the server exchange keys and agree on a cipher suite to encrypt and decrypt the data transmitted over the network. References := Cisco Cybersecurity Source Documents

A host-based firewall is a utility that can block unauthorized access to a computer system, including port scans. It monitors incoming and outgoing network traffic and permits or blocks data packets based on a set of security rules.

According to the NIST Computer Security Incident Handling Guide, the next step in handling an event after confirming a potential indicator of compromise on an endpoint is to collect public information on the malware behavior. This step involves searching for information from various sources, such as antivirus vendors, security blogs, threat intelligence feeds, and online forums, to learn more about the characteristics, capabilities, and impact of the malware. This information can help the SOC team to identify the type, severity, and scope of the incident, as well as to determine the appropriate response actions and mitigation strategies.
Isolating the infected endpoint, performing forensics analysis, and prioritizing incident handling are subsequent steps that follow after collecting public information on the malware behavior. References:
* Computer Security Incident Handling Guide
* SP 800-61 Rev. 2, Computer Security Incident Handling Guide