Inboxfuscation: Because Rules Are Meant to Be Broken
a day ago
- #unicode-obfuscation
- #cybersecurity
- #email-security
- Microsoft Exchange inbox rules are a critical attack vector for APT groups.
- Inboxfuscation is a Unicode-based obfuscation technique to evade detection.
- Four primary Unicode obfuscation techniques: Character Substitution, Zero-Width Injection, Bidirectional Text Manipulation, and Hybrid Techniques.
- Functional obfuscation tricks include forwarding emails to the Calendar folder and using null characters.
- Theoretical attack scenarios include long-term data exfiltration and anti-forensics operations.
- Current detection limitations include ASCII-based pattern matching and limited Unicode awareness.
- Advanced detection methodology involves character category analysis and multi-format log analysis.
- Defensive framework supports multiple Exchange log formats and provides structured output for SIEM integration.
- Research highlights gaps in email security postures, including detection blind spots and compliance risks.
- Open-source Inboxfuscation framework helps simulate, detect, and mitigate obfuscated mailbox rules.