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.
Here's how ThreatNG helps address the cybersecurity concerns related to RPC APIs:
ThreatNG excels in external discovery. It can perform purely external unauthenticated discovery, meaning it doesn't need internal connectors to find assets.
This is crucial for RPC API security because it allows security teams to identify exposed RPC endpoints they might not know. Many RPC API vulnerabilities arise simply because organizations don't know where their RPC APIs are exposed.
For example, ThreatNG can discover subdomains and identify services running on various ports, which could reveal previously unknown RPC API endpoints.
ThreatNG provides a broad range of external assessment capabilities that are highly relevant to RPC API security:
Cyber Risk Exposure: ThreatNG considers various parameters, including exposed sensitive ports, to determine cyber risk exposure. Exposed RPC ports would directly contribute to this risk score, highlighting a potential vulnerability.
For instance, if ThreatNG discovers an exposed RPC service on a non-standard port without proper security headers, it will flag this as a high cyber risk.
Vulnerability Scanning: ThreatNG's assessment includes known vulnerabilities. This means it can identify if the discovered RPC services have known weaknesses that attackers could exploit.
For example, if an older version of an RPC protocol with known vulnerabilities is detected, ThreatNG will report this.
Domain Intelligence: ThreatNG uses Domain Intelligence, which includes subdomain enumeration and DNS record analysis. This helps map the attack surface and identify potential entry points for attacks targeting RPC APIs.
For instance, ThreatNG can find subdomains hosting RPC services by analyzing DNS records and identify potential misconfigurations.
Technology Stack Analysis: ThreatNG identifies the technologies used by an organization. Knowing the specific RPC technology is crucial for assessing its security posture.
For example, if ThreatNG identifies a vulnerable or outdated RPC implementation as part of the technology stack, security teams can focus their remediation efforts.
3. Reporting
ThreatNG provides various reporting options, including technical and prioritized reports. These reports can highlight specific RPC API vulnerabilities and the associated risks, enabling security teams to take action.
For example, a report could list all exposed RPC endpoints, their associated vulnerabilities, and a prioritized list of remediation steps.
ThreatNG offers continuous monitoring of the external attack surface. This is essential for RPC API security because it allows organizations to detect new exposures or vulnerabilities as soon as they arise.
For instance, ThreatNG will detect and alert the security team if a new RPC service is inadvertently exposed.
ThreatNG's investigation modules provide detailed information that is crucial for analyzing and mitigating RPC API related risks:
Domain Intelligence: This module provides a wealth of information, including:
Subdomain Intelligence: This includes identifying ports and known vulnerabilities. For example, it can reveal exposed RPC ports (e.g., port 135 for DCE/RPC) and identify vulnerable services running on those ports.
IP Intelligence: This helps identify the servers hosting RPC services and their associated information.
Sensitive Code Exposure: ThreatNG discovers code repositories and their exposure level, and investigates the contents for sensitive data. This is relevant because RPC API credentials or configuration details might be inadvertently exposed in code repositories.
For example, ThreatNG might find a GitHub repository containing an application's source code with hardcoded RPC credentials.
Mobile Application Discovery: ThreatNG discovers mobile apps and analyzes them for sensitive information. This is important because mobile apps might communicate with RPC APIs and contain hardcoded credentials or other vulnerabilities.
For example, ThreatNG could identify a mobile app that uses an RPC API for data synchronization and discover exposed API keys within the app's code.
Search Engine Exploitation: ThreatNG helps identify an organization’s susceptibility to exposing information via search engines. This is relevant because attackers might use search engines to find exposed RPC endpoints or related information.
For example, ThreatNG can help identify if search engines are indexing pages that reveal internal RPC server details.
ThreatNG's intelligence repositories contain valuable data that can aid in RPC API security:
Dark Web Presence: This includes compromised credentials. If credentials used by an RPC service are found on the dark web, it indicates a high risk of unauthorized access.
Known Vulnerabilities: This information helps identify vulnerable RPC implementations.
7. Working with Complementary Solutions
ThreatNG is designed to work with complementary security solutions.
For example, ThreatNG can discover exposed RPC APIs and hand this information to other security solutions for further analysis and protection.
This allows for a layered defense, where ThreatNG provides the initial discovery and other tools provide more specialized security functions.
Examples of ThreatNG Helping
Identifying Shadow RPC APIs: ThreatNG can discover RPC APIs deployed without proper authorization or documentation, helping to eliminate shadow IT risks.
Prioritizing Remediation: By assessing the cyber risk exposure associated with different RPC APIs, ThreatNG helps security teams prioritize their remediation efforts.
Detecting Data Leaks: ThreatNG can detect if sensitive data related to RPC APIs, such as credentials or configuration files, are exposed in code repositories or other public sources.
Examples of ThreatNG Working with Complementary Solutions
SIEM Integration: ThreatNG can send alerts about exposed RPC APIs and vulnerabilities to a SIEM (Security Information and Event Management) system for centralized logging, monitoring, and correlation with other security events.
Vulnerability Management Integration: ThreatNG's vulnerability findings can be integrated with a vulnerability management system to track remediation efforts and promptly address RPC API vulnerabilities.
API Security Gateways: ThreatNG can provide information about exposed RPC APIs to API security gateways, which can then enforce authentication, authorization, and rate limiting to protect those APIs.
