Analyzing Macro Malware In Office Documents

Analyzing Macro Malware In Office Documents

Overview

Cybersecurity skill for analyzing macro malware in office documents. Follows industry best practices and security standards.

When to Use

Trigger phrases:

• "analyzing macro malware in office documents"

• "Analyzes malicious VBA macros embedded in Microsoft Office documents (Word, Exce"

• A suspicious Office document (.doc, .docm, .xls, .xlsm, .ppt) has been flagged by email security

• Investigating phishing campaigns that deliver weaponized Office documents

• Extracting VBA macro code to identify the payload download URL and execution method

• Analyzing obfuscated VBA code to understand the full attack chain

• Determining if a document uses DDE, ActiveX, or remote template injection instead of macros

Do not use for analyzing non-macro Office threats (DDE, remote template injection); while this skill covers detection of these, specialized analysis may be needed.

When NOT to Use

• When you lack proper authorization for testing
• For production systems without change management
• When the task requires legal or compliance expertise beyond technical scope

Prerequisites

• Python 3.8+ with oletools installed (pip install oletools)
• oledump.py from Didier Stevens (https://blog.didierstevens.com/programs/oledump-py/)
• Isolated analysis VM without Microsoft Office installed (prevents accidental execution)
• XLMDeobfuscator for Excel 4.0 macro analysis (pip install xlmdeobfuscator)
• LibreOffice for safe document rendering (does not execute VBA macros by default)

Workflow

# Example: IOC detection
import re

IOC_PATTERNS = {
    "ip": r"\b(?:\d{1,3}\.){3}\d{1,3}\b",
    "domain": r"\b[a-z0-9-]+\.[a-z]{2,}\b",
    "hash_md5": r"\b[a-f0-9]{32}\b",
    "hash_sha256": r"\b[a-f0-9]{64}\b",
}

def extract_iocs(text: str) -> dict:
    return {k: re.findall(v, text) for k, v in IOC_PATTERNS.items()}

1. Scope the Analysis — Define what macro malware in office documents artifacts or data sources to examine and the investigation timeline.
2. Preserve Evidence — Create forensic copies of relevant data. Maintain chain of custody documentation.
3. Extract Key Indicators — Parse and extract relevant macro malware in office documents data points from collected artifacts.
4. Correlate Findings — Cross-reference extracted data with other sources (threat intel, logs, timelines).
5. Build Timeline — Construct a chronological sequence of events related to macro malware in office documents.
6. Document Analysis — Write findings report with evidence, conclusions, and recommendations.

Tools

• Forensic Toolkit — Evidence collection and analysis
• Timeline Tools — Chronological event reconstruction
• Log Analysis Platform — Centralized log parsing and search

Process

1. Reconnaissance — Gather target information, identify attack surface, enumerate services
2. Analysis/Exploitation — Execute the technique, analyze results, document findings
3. Reporting — Document IOCs, write findings, provide remediation recommendations

Verification

• All macro malware in office documents procedures executed completely and documented
• Findings validated against multiple data sources
• False positives identified and filtered
• Results documented with evidence and timestamps
• Recommendations provided with risk-based prioritization

Anti-Rationalization Table