Rpcbind Portmapper Detection Scanner

Rpcbind Portmapper is a widely used service in Unix-like systems, essential for mapping RPC program numbers to network port numbers. It is typically deployed in environments where network services rely on RPC (Remote Procedure Call) communications, helping clients locate the servers for requested services easily. System administrators, network engineers, and IT professionals use Rpcbind for service management and resource allocation in networked systems. While Rpcbind is crucial for legitimate network operations, its presence can be a valuable information source for an attacker trying to map out network services. Understanding the use of Rpcbind in an infrastructure can aid in effectively securing network communications.

The detection in this template is the exposure of the Rpcbind Portmapper service, which may inadvertently disclose information about network services. This exposure can aid attackers in performing network reconnaissance, potentially leading to further exploitation attempts. Detecting the Rpcbind service is a key step in securing network infrastructures, as it informs administrators about potential undisclosed open services. The detection helps in assessing security posture and devising strategies for mitigating associated risks. Misconfigured or exposed Portmapper services can be leveraged by attackers for network mapping without complex authentication measures.

Technically, the Rpcbind portmapper service typically listens on port 111 and can map requests to remote services using RPC. The presence of "/run/rpcbind.sock" or similar endpoints is indicative of Rpcbind's operation on the system. Attackers may exploit insecure Rpcbind configurations to gain insights into available services and potential vulnerabilities. The straightforward detection of Rpcbind involves examining whether certain packets elicit specific responses from the service, confirming its activity. Proper configuration and monitoring of Rpcbind are essential to mitigate risks associated with its exposure.

Potential effects of an exposed Rpcbind service include unauthorized network mapping, which might lead to identifying exploitable services, resulting in broader network penetration. Malicious actors can exploit Rpcbind to deduce the structure of an organization's network, identifying weak points and planning attacks. In extreme cases, it could facilitate targeted exploitation, resulting in unauthorized access to sensitive data. Proactively managing Rpcbind services helps to prevent such information leakage, reducing the attack surface significantly. A secure approach involves configuring Rpcbind to limit information exposure and access to only essential network segments.

REFERENCES

• https://book.hacktricks.xyz/pentesting/pentesting-rpcbind