rbndr is a lightweight DNS server designed to facilitate testing for DNS rebinding vulnerabilities. It responds to DNS queries by dynamically selecting an IP address from a pre-defined set and providing it with a very low TTL (Time-To-Live). This allows developers to evaluate how software handles situations where the IP address associated with a hostname can change unpredictably. The service leverages a simple DNS server implementation to expose the core vulnerability.
rbndr offers a straightforward way to create and test DNS rebinding scenarios without needing to configure a full-fledged DNS server. It's particularly useful for testing software susceptible to TOCTOU attacks, enabling developers to identify and address security flaws related to hostname-based access control. Its minimal footprint makes it easy to deploy and integrate into testing workflows.
- Random IP Resolution: The service resolves hostnames to a randomly selected IP address, simulating inconsistent address assignments.
- Simple Configuration: Requires minimal setup; just need to identify the desired IP addresses.
- Low TTL: Uses a low TTL to encourage frequent DNS lookups and expose the timing-sensitive nature of the vulnerability.
- Base-16 Encoding: Uses base-16 encoding for IP addresses, offering a unique way to represent addresses.
- Easy to Use: Simple
hostcommand interface for testing DNS rebinding scenarios. - Cross-Platform: Designed to be compatible with various operating systems and environments.
- Portable: Can easily be deployed on different machines or cloud instances.
rbndr is a mature project with a history dating back to 2016, indicated by its creation date and last commit. While not actively updated recently, it remains stable and reliable for its intended purpose. The project has a solid reputation as a testing tool for security researchers and developers, and the core functionality is well-established.
rbndr is beneficial for security researchers and developers who want to assess their software's vulnerability to DNS rebinding attacks. It helps identify weaknesses in applications that rely on hostname-based security checks. By providing a simple and reliable tool for generating dynamic DNS responses, rbndr facilitates robust testing and strengthens application security.