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

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).

According to the MITRE ATT&CK matrix, when encrypted traffic is tunneled through a legitimate protocol such as HTTP (port 80) to a non-malicious domain, this aligns with the tactic “Exfiltration Over Asymmetric Encrypted Non-C2 Protocol” (T1048.002). The attacker is trying to hide exfiltration in otherwise benign traffic.

The eradication phase in incident response involveseliminating the root cause of the incidentand strengthening defenses to prevent reoccurrence. In this case:

Intrusion Prevention System (D): Adding new rules to the IPS to detect and block malicious activity on TCP/135 is a direct eradication step to remove the threat’s entry point and prevent future attacks.

Centralized User Management (C): Hardening user accounts, removing unnecessary permissions, and applying tighter authentication/authorization measures helps eliminate the possibility that threat actors could exploit weak or mismanaged accounts to continue accessing the system.

Althoughanti-malware software (A)andenterprise block listing (E)are valuable, themost direct eradication stepshere specifically involve managing network access (via IPS) and strengthening user controls (via centralized user management), especially when TCP/135 (MSRPC endpoint mapper) can be used to enumerate services and potentially access vulnerable endpoints remotely.

This aligns with best practices outlined in incident response frameworks (such as the NIST SP 800-61 and referenced resources), which emphasizeclosing the exploited entry points(in this case, TCP/135) andremoving any lingering access pointsthrough user management and network control enhancements.

Since the phishing email originates from a known compromised cloud provider (XYZCloud), the correct immediate action for the security analyst is to determine the broader scope of exposure. This involves checking whether other users in the organization received similar emails from the same potentially malicious source. Therefore, querying for emails from theIP address rangesorSMTP domainslinked to XYZCloud is essential for identifying other possible attack vectors.

This step aligns with the containment phase of the incident response lifecycle, as outlined in theCyberOps Technologies (CBRFIR) 300-215 study guide, where threat hunting and log analysis are used to determine the extent of compromise and prevent lateral movement or further exposure. Only after the scope is understood should remediation or reporting actions follow.

The syntax in the code snippet includes:

On Error Resume Next– a classic VBScript error-handling directive.

function ... end functionstructure.

Use ofMid(),Chr(), andAsc()functions – all commonly used in VBScript for string manipulation.

CInt()for conversion – typical in VBScript.

These characteristics alignexactly with VBScript, which is frequently used in malicious macros and obfuscated payloads for malware distribution, as covered in the Cisco CyberOps Associate curriculum when analyzing scripts and encoded threats.

From the exhibit, the first artifact (PE32 executable fromsyracusecoffee.com) and the second artifact (HTML fromqstride.com) suggest astaged malware deliverymethod. The executable and the HTML file are linked to different domains, often indicating redirection or multi-stage infection strategies, which is common in phishing or malvertising campaigns.

The Cisco guide explains this tactic as:“One file may appear benign but can initiate downloads or connections to external resources to fetch additional payloads or redirect users”. This pattern of domain redirection strongly supportsOption B.

Process injectionis a tactic where malicious code is inserted into the memory space of another process, enabling it to run with the privileges and context of a legitimate application. The Cisco study guide explains that this method allows malware to "hide in plain sight" within trusted processes and evade endpoint detection and response (EDR) tools.

It specifically notes:"Process injection techniques allow malware to execute within the memory space of a legitimate process, avoiding detection and taking advantage of the process's permissions.".

The Wireshark capture shows a series of HTTP requests and responses:

The client (10.1.21.101) sends a GET request for/Lk9tdZ.

The server (209.141.51.196) responds withHTTP/1.1 302 Found, which is a standard HTTP status code indicating a redirection.

The subsequent GET request from the client is for/files/1.bin, which indicates it followed the redirect.

This behavior confirms that the server is issuing an HTTP 302 redirect from the initial request path/Lk9tdZto/files/1.bin. This is often observed in malware command-and-control behavior or file download staging.

Option A is incorrect: 302 is a status code, not a data size.

Option C is incorrect: port 49723 is a source/destination ephemeral port, not a redirect target.

Option D is incorrect: communication is over HTTP, not HTTPS (which would indicate encryption).