CompTIA CS0-003 - CompTIA CyberSecurity Analyst CySA+ Certification Exam

A security analyst’s concern is that any discovered vulnerabilities in the OS that is approaching the end-of-life date will not be remediated by the vendor, leaving the system exposed to potential attacks. The other options are not directly related to the security analyst’s role or responsibility. Verified References: CompTIA Cybersecurity Analyst (CySA+) Certification Exam Objectives, page 9, section 2.21

This log shows multiple 404 errors being triggered from requests to different directories or paths, which strongly suggests adirectory brute-force attack. In this type of attack, an adversary uses automated tools to enumerate directory or file paths in an attempt to find hidden or misconfigured resources. The frequent 404 “Not Found” HTTP responses from a single IP address attempting to access different URL paths is the signature pattern for directory brute-forcing. This behavior is not consistent with XSS, SQLi, or RCE, which would involve payloads or specific encoded commands, not merely probing paths.

The best action for the incident response team to recommend in this scenario is to perform no action until HR or legal counsel advises on next steps. This action can help avoid any potential legal or ethical issues, such as violating employee privacy rights, contractual obligations, or organizational policies. This action can also help ensure that any evidence or information collected from the employee’s system or network is admissible and valid in case of any legal action or dispute. The incident response team should consult with HR or legal counsel before taking any action that may affect the employee’s system or network.

Command-and-control (C2) beaconing involves compromised systems communicating with an attacker’s server at regular intervals, often using HTTPS to blend in with legitimate traffic. This is indicative of a potential compromise where malware communicates back to a command center. The persistent nature of the connections after hours and throughout the day suggests automated beaconing, which is a tell-tale sign of C2 activity. According to CompTIA CySA+, this type of activity should raise immediate suspicion and warrants further investigation and containment. While options B, C, D, and E might indicate other issues, they do not fit the pattern described as well as option A.

Agent-based vulnerability scanning is a method that involves installing software agents on the target systems or networks that can perform local scans and report the results to a central server or console. Agent-based vulnerability scanning can reduce network traffic, as the scans are performed locally and only the results are transmitted over the network. Agent-based vulnerability scanning can also provide more accurate and up-to-date results, as the agents can scan continuously or on-demand, regardless of the system or network status or location.

The MITRE ATT&CK framework is a knowledge base of cybercriminals’ adversarial behaviors based on cybercriminals’ known tactics, techniques and procedures (TTPs). It helps security teams model, detect, prevent and fight cybersecurity threats by simulating cyberattacks, creating security policies, controls and incident response plans, and sharing information with other security professionals. It is an open-source project that evolves with input from a global community of cybersecurity professionals1. References: What is the MITRE ATT&CK Framework? | IBM

Quarantining the server is the best action to perform immediately, as it isolates the affected server from the rest of the network and prevents the ransomware from spreading to other systems or data. Quarantining the server also preserves the evidence of the ransomware attack, which can be useful for forensic analysis and law enforcement investigation. The other actions are not as urgent as quarantining the server, as they may not stop the ransomware infection, or they may destroy valuable evidence. Shutting down the server may not remove the ransomware, and it may trigger a data deletion mechanism by the ransomware. Reimaging the server may restore its functionality, but it will also erase any traces of the ransomware and make recovery of encrypted data impossible. Updating the OS to the latest version may fix some vulnerabilities, but it will not remove the ransomware or decrypt the data. Official References:

https://www.cisa.gov/stopransomware/ransomware-guide

https://www.cisa.gov/sites/default/files/publications/Ransomware_Executive_One-Pager_and_Technical_Document-FINAL.pdf

https://www.cisa.gov/stopransomware/ive-been-hit-ransomware

The function that would help the analyst identify IP addresses from the same country is:

function x() { info=$(geoiplookup $1) && echo “$1 | $info” }

This function takes an IP address as an argument and uses the geoiplookup command to get the geographic location information associated with the IP address, such as the country name, country code, region, city, or latitude and longitude. The function then prints the IP address and the geographic location information, which can help identify any IP addresses that belong to the same country.