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

The alert shown is based on aSnort rulefor aUnicode directory traversal attack against IIS web servers(Microsoft platform). The key detail here is the payload content"../..%c0%af../"which is a classic IIS-specific exploit related toCVE-2000-0884.

Since the company only usesUnix systems, they arenot vulnerableto this IIS-specific attack. Therefore, these alerts are triggered by irrelevant traffic or misapplied signatures, resulting inFalse Positives.

As defined in the Cisco CyberOps guide:

“False Positive: an alert is generated for traffic that is not actually malicious or relevant to the protected environment”.

The observed process tree (AcroRd32.exe→cmd.exe→powershell.exe) strongly suggestsmalicious behavior, particularly inPDF-based malware attacksleveraging embedded scripts or exploits.

Ais correct: Submitting the suspicious PDF toCisco Threat Gridallows sandbox analysis to detect hidden malicious behaviors.

Dis correct: The suspicious activity warrantsquarantining the hostto contain potential spread or further compromise.

Using adifferent IP addressto disguise the origin of an attack is the definition ofIP spoofing.

“Spoofing involves falsifying data, such as IP or MAC addresses, to hide the source of malicious activity.” — Cisco CyberOps guide

The hexadecimal representation in the exhibit does not match the Base64 encoding format, which uses ASCII characters (A-Z, a-z, 0-9, +, /) and often includes padding with=. This string is clearly hex and is more aligned withCharcode, where hexadecimal values represent individual characters based on ASCII values.

The Cisco CyberOps Associate guide refers to such encodings during forensic analysis and emphasizes identifying patterns in memory dumps, payloads, or logs. "Security professionals often decode hexadecimal strings to reveal ASCII representations, particularly when inspecting encoded payloads or character obfuscation techniques used in malware".

Comprehensive and Detailed Explanation:

The log entries show repeated SSH login attempts for various invalid usernames (e.g., admin, phoenix, rainbow, test, user, etc.) from different source ports. These are clear signs of a brute-force attack—an automated process trying multiple usernames and passwords in hopes of gaining access.

Mitigating such attacks includes:

Implementing account lockout policies (e.g., locking an account after several failed login attempts).

Enabling Multi-Factor Authentication (MFA) to ensure that password guessing alone is insufficient for account access.

Therefore, the correct answer is:

D. Brute-force attack; implement account lockout policies and roll out MFA.

The log entry shows a failed SSH login attempt for an invalid user “admin” from IP192.168.1.100. As the system has just gone live and no legitimate use is expected, this could be an early reconnaissance or brute-force attempt. However, blocking IPs or resetting passwords without fully understanding the context could lead to incomplete remediation or false positives.

According to Cisco CyberOps best practices, the first step is to thoroughly investigate the alert by correlating it with other logs (e.g., authentication logs, IDS/IPS logs) to determine the intent and scope of activity.

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In therecovery phase, the goal is to restore affected systems to normal operations and ensure the threat has been completely eradicated. According to the CyberOps Associate guide:

"This phase may include restoring data from clean backups, replacing compromised systems, and the re-installation of the Operating System (OS) and applications".

Also:

"During recovery, scanning hosts with updated antivirus and removing vulnerabilities ensures systems do not get reinfected".

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.