Full Report
With our recent release of BiDiBLAH 2.0, we’ve decided to revisit some real world scenarios, and ways BiDiBLAH can deal with it… All the scenarios can be downloaded from the BiDiBLAH home page. Scenario: If a hacker can mine/collect email addresses from our company he/she can send malware / phishing attacks to these people. But, who are these people? And what other sensitive information are we leaking from a particular domain? Solution:
Analysis Summary
# Tool/Technique: BiDiBLAH 2.0
## Overview
BiDiBLAH 2.0 is a tool designed to automate the discovery and collection of publicly accessible information related to a target domain, specifically focusing on enumerating valid email addresses and associated DNS names. The primary purpose highlighted in this scenario is to determine potential attack surfaces for subsequent malware or phishing campaigns by identifying employee/domain contacts.
## Technical Details
- Type: Tool
- Platform: Not explicitly stated, but implies interaction with external services (internet/DNS) to harvest data. Likely uses standard scripting environments.
- Capabilities: Email address enumeration, DNS name enumeration associated with a domain.
- First Seen: The article references the recent release of version 2.0 (around March 2009, based on publication date).
## MITRE ATT&CK Mapping
The primary focus of BiDiBLAH aligns with initial reconnaissance activities conducted prior to a direct attack.
- **TA0043 - Reconnaissance**
- **T1598 - Gather Victim Identity Information**
- T1598.001 - Email Accounts: Identifying valid email addresses for phishing.
- **T1592 - Gather Victim Information**
- T1592.005 - DNS Information: Discovering associated DNS names.
## Functionality
### Core Capabilities
- **Email Address Enumeration:** Finding which email addresses are valid or can be allocated within a target domain (e.g., `supercorp123.com`).
- **DNS Name Discovery:** Identifying various DNS names associated with the target domain.
### Advanced Features
The context suggests an efficient (5 minutes for the example domain) way to gather this specific intelligence, leveraging network introspection or external lookups (implied by the goal of finding what can be "allocated from the internet").
## Indicators of Compromise
As BiDiBLAH is a passive reconnaissance tool focused on querying public infrastructure (like DNS servers), it typically does not generate traditional malware IOCs like file hashes or specific C2 infrastructure unless the network querying itself is flagged.
- File Hashes: N/A (Tool setup/execution dependent)
- File Names: N/A
- Registry Keys: N/A
- Network Indicators: Tool execution would involve DNS queries and potentially HTTP/SMTP lookups targeting the victim's domain infrastructure, though specific malicious indicators are unlikely unless it exploits a vulnerability during the query process.
- Behavioral Indicators: High volume of DNS queries or attempts to query non-existent user mailboxes (if leveraging SMTP verification).
## Associated Threat Actors
The article does not name specific threat actors using BiDiBLAH; it is presented as a tool released by SensePost for security testing and scenario validation.
## Detection Methods
Detection would focus on monitoring outgoing network activity from the querying machine during tool execution.
- Signature-based detection: Signatures tailored to the BiDiBLAH execution file (if known).
- Behavioral detection: Detection of processes rapidly performing common lookups (e.g., large batches of MX record queries, or attempts to check email validity via non-standard protocols if the tool employs such methods).
- YARA rules: Not available from context.
## Mitigation Strategies
Mitigation focuses on preventing the successful harvesting of this data through configuration and monitoring.
- Prevention measures: Implementing strict rate limiting on external DNS servers to slow down automated enumeration attempts.
- Hardening recommendations: Minimizing publicly exposed user information, potentially utilizing catch-all email acceptance only internally, or filtering SMTP responses that confirm user existence.
## Related Tools/Techniques
Tools that perform open-source intelligence (OSINT) gathering and user enumeration:
- Social-Engineer Toolkit (SET)
- TheHarvester
- Recon-ng