RPC API
In the context of security and cybersecurity, RPC APIs (Remote Procedure Call APIs) offer a mechanism for applications to execute procedures on a remote server. They provide a way to extend functionality and enable communication between programs on different machines. However, this functionality also introduces security considerations that need to be addressed.
Here's a breakdown of RPC APIs and their security implications:
RPC API Fundamentals:
Procedure Calls: RPC APIs allow applications to call procedures on remote servers as local procedures. It simplifies development but requires careful security measures.
Communication Protocols: Different RPC implementations use protocols, including TCP/IP, HTTP, and proprietary protocols. The security of the communication depends on the chosen protocol and its implementation.
Distributed Nature: The distributed nature of RPC APIs introduces additional security challenges compared to local procedure calls.
Security Considerations for RPC APIs:
Authentication and Authorization: Robust authentication and authorization mechanisms ensure that only authorized applications can execute procedures on the remote server.
Data Encryption: Data transmitted between the client and server should be encrypted (especially when using non-secure protocols like plain TCP/IP) to prevent eavesdropping and man-in-the-middle attacks.
Input Validation: All user input and data passed through the RPC API should be thoroughly validated to prevent attacks like code injection on the remote server.
Network Security: Securing the communication channels used by the RPC protocol is essential. It might involve firewalls and network segmentation to restrict access to the RPC server.
Securing RPC APIs:
Secure Communication Protocols: Use protocols like HTTPS for RPC communication whenever possible.
Strong Authentication and Authorization: Implement robust mechanisms to verify the caller's identity and enforce access control for different procedures.
Input Validation: Validate all data passed through the RPC API to prevent remote code execution attacks on the server.
Network Segmentation: Segment the network to restrict access to the RPC server only from authorized applications.
Regular Security Testing: Regularly test RPC APIs for vulnerabilities to identify and address potential security risks.
RPC APIs offer a powerful way to extend application functionality, but security needs to be a top priority. Organizations can leverage the benefits of RPC APIs while mitigating security risks by adhering to secure coding practices, implementing robust authentication and authorization, using secure communication protocols, and following additional security measures.
ThreatNG and RPC API Security: Discovery as the Initial Step
ThreatNG, with its external attack surface management (EASM) capabilities, plays a vital role in securing RPC APIs by focusing on discovery. Here's how it helps organizations manage and secure these APIs through pure discovery, interacts with complementary solutions, and creates a comprehensive defense:
1. Uncovering Hidden RPC Endpoints:
ThreatNG scans the external environment, identifying all exposed RPC API endpoints accessible from outside the organization's network.
This discovery is crucial because many security vulnerabilities with RPC APIs arise simply because the security team was unaware of them. Due to their diverse communication protocols, traditional security tools might need help to detect these APIs.
2. Handoff to Specialized Solutions:
ThreatNG acts as the initial investigator, uncovering exposed APIs, and then hands off the information to other security solutions for further analysis and protection:
Security Information and Event Management (SIEM): ThreatNG shares the discovered RPC API inventory with SIEM solutions. SIEM can analyze logs generated during RPC communication, potentially identifying suspicious activity or unauthorized access attempts.
Network Detection and Response (NDR): ThreatNG can inform NDR solutions about the discovered RPC APIs and communication protocols. NDR can then monitor network traffic for potential attacks targeting the protocols used by the RPC APIs (e.g., unusual traffic patterns on ports used for proprietary RPC protocols).
3. Example: Securing a Legacy HR System's RPC API
Imagine ThreatNG discovers an exposed RPC API for a legacy HR system. This API might use a non-secure communication protocol (like plain TCP/IP) and lack proper authentication.
ThreatNG to SIEM: ThreatNG shares the API details and communication protocol with the SIEM solution.
SIEM Analysis: The SIEM analyzes logs related to the RPC communication and identifies suspicious activity, such as a high volume of login attempts from unauthorized locations.
Action: Based on the combined information (discovery and SIEM alerts), IT can prioritize immediate action. They can:
Secure the API: Work with the HR team to migrate the RPC API to a secure protocol (e.g., HTTPS) and robust strong authentication mechanisms.
Restrict Access: Limit access and communication to specific IP addresses.
4. Benefits of Discovery-Driven Approach:
Reduced Attack Surface: ThreatNG exposes hidden RPC APIs, allowing organizations to identify and secure them before attackers exploit them.
Prioritized Security Monotocols, ThreatNG helps organizations focus SIEM and NDR monitoring efforts on the most critical by highlighting newly discovered APIs and their communication protocol areas.
Streamlined Security Management: The handoff to complementary solutions allows for further analysis, anomaly detection, and targeted security measures based on the specific communication protocol used by the RPC API.
ThreatNG is the foundation for RPC API security by providing a complete view of all externally accessible RPC endpoints. This discovery power allows other security solutions to take informed actions based on the communication protocol, ultimately creating a layered defense against attacks that target RPC APIs.
