Full Report
Quick update on your favourite brute forcer… The file input “MS EOF char” issue has been resolved, and provision has been made for blank passwords too. The above mentioned error meant that Crowbar incorrectly used EOF characters on *nix based files. Regarding the blank passwords, simply include the word “[blank]” (without the “”) in your brute force file and crowbar will test for blank usernames/passwords as well. For those of you that don’t know, Crowbar is a generic brute force tool used for web applications. It’s free, it’s light-weight, it’s fast, it’s kewl :>
Analysis Summary
# Tool/Technique: Crowbar
## Overview
Crowbar is a generic, free, lightweight, and fast brute-forcing tool specifically designed for attacking web applications. This update (version 0.941) addresses two key issues: resolution of an "MS EOF char" error affecting *nix-based input files, and the addition of support for brute-forcing blank passwords.
## Technical Details
- Type: Tool
- Platform: Web Applications (implied, target environment)
- Capabilities: Brute-forcing credentials against web applications, supporting Unix-style input files, and testing for blank passwords.
- First Seen: Not explicitly stated, but version 0.941 was published on August 15, 2008.
## MITRE ATT&CK Mapping
The primary function of Crowbar aligns with initial access or credential access phases.
- **T1590 - Initial Access (Implied)**
- **T1590.001 - External Remote Services** (If targeting login portals exposed publicly)
- **T1110 - Brute Force**
- **T1110.001 - Password Guessing**
- **T1110.003 - Password Guessing: Automated** (As Crowbar automates the process)
## Functionality
### Core Capabilities
- **Generic Web Application Brute-Forcing:** Designed to test various login mechanisms on web applications.
- **Input Handling Correction:** Fixed an issue where the "MS EOF char" caused incorrect parsing on *nix-based input files, ensuring better compatibility with Unix/Linux style password lists.
### Advanced Features
- **Blank Password Testing:** Allows testers to include the literal string `[blank]` in the username/password input file to specifically test for credentials where the username or password field is empty.
## Indicators of Compromise
*Note: As Crowbar is a benign security tool being updated, IoCs relate to its configuration rather than malware artifacts.*
- File Hashes: N/A (Not provided in context)
- File Names: crowbar (Implied name)
- Registry Keys: N/A
- Network Indicators: N/A (Relies on user-supplied lists for targets)
- Behavioral Indicators: High volume, sequential login attempts against web application endpoints.
## Associated Threat Actors
This tool is primarily associated with penetration testers or ethical hackers testing application security. It is not explicitly linked to specific malicious threat actor groups mentioned in this context.
## Detection Methods
- **Signature-based detection:** Detecting the execution of the Crowbar executable (if signatures exist).
- **Behavioral detection:** Monitoring web server access logs for an unusually high rate of failed login attempts against a single path/endpoint from a single source IP address, characteristic of password spraying or brute-forcing.
- **YARA rules:** N/A (Not provided)
## Mitigation Strategies
- **Prevention measures:** Implementing strong, complex password policies.
- **Hardening recommendations:**
1. Implementing account lockout policies after a small number of failed attempts.
2. Using CAPTCHA or other similar controls on login forms to thwart automated tools like Crowbar.
3. Rate-limiting login requests per IP address.
## Related Tools/Techniques
- Hydra (Similar generic network logon cracker)
- Nmap Scripting Engine (NSE) scripts related to brute-forcing login pages.