300-215 Exam Dumps : Conducting Forensic Analysis and Incident Response Using Cisco CyberOps Technologies (CBRFIR v1.2)

According to the CyberOps Technologies (CBRFIR) 300-215 study guide curriculum, 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 string in the exhibit is a classic example of Base64 encoding. Base64 is used to encode binary data into ASCII characters, making it suitable for transmitting data over media that are designed to deal with textual data. It typically ends with one or two equal signs = (padding), which this string does. This format is commonly seen in obfuscated payloads or malware communications in the wild.

The Apache access logs in the exhibit show a sequence of HTTP requests and responses indicative of a malicious upload via WordPress:

A POST to:

/wp-admin/admin-ajax.php with parameters that include uploading r57.php (a known PHP web shell).

The uploaded file name appears as r57.php in:→ &name=%5B%5D=r57.php&FILES...

There are plugin installation and activation attempts, specifically for:

file-manager plugin:→ plugin=file-manager&...

Which is known to be vulnerable and exploited for file uploads.

GET requests to:

/wp-content/57.php and variations such as 57.php?28 — This suggests that r57.php was successfully uploaded and is being accessed.

These logs reveal that:

D. The attacker used the WordPress file manager plugin to upload r57.php — confirmed by plugin activity and file uploads.

B. The attacker uploaded the WordPress file manager trojan — as evidenced by the direct access to /wp-content/57.php (r57 shell variant).

Other options are invalid or speculative:

A is correct in identifying r57 as a web shell, but the logs don't show privilege escalation.

C mentions brute force and SQL injection, which are not indicated here.

E assumes legitimate access — logs suggest exploitation, not standard login.