Routing protocols have long been a crucial component of the Internet, enabling the efficient and seamless transfer of data across networks. However, these protocols were originally developed without much consideration for security. This oversight has led to numerous vulnerabilities that can be exploited by attackers to disrupt services and compromise network security.
One such protocol is the Border Gateway Protocol (BGP), which initially did not anticipate the potential for attacks between peers. While efforts have been made to address origin and path validation in BGP, the security of BGP implementations, particularly message parsing, has been neglected. As a result, multiple vulnerabilities have emerged, posing a significant risk of denial-of-service attacks.
Unfortunately, there has been a prevailing attitude within the security industry that if a particular aspect of a system is not broken, there’s no need to address it. As a result, security auditing often fails to thoroughly examine all the software and devices on a network, creating blind spots. This is especially true when organizations are unaware that routing protocols are in use within their infrastructure. These protocols can be found not only in traditional endpoints and servers but also in data centers, VPNs, and even embedded in custom appliances.
In recent times, there has been an increasing focus on the security of network devices, including routers, as they have become prime targets for threat actors. The US Cybersecurity and Infrastructure Security Agency (CISA) has deemed it necessary for federal agencies to mitigate the risks associated with these devices. However, these efforts bring to light concerns about the security of the underlying routing protocols. Threat actors have been known to leverage routers for reconnaissance, malware deployment, and command and control communications. Moreover, CISA’s known exploited vulnerabilities catalog includes three BGP denial-of-service issues, along with two others affecting different routing protocols.
BGP hijacks and leaks are another source of concern, as they can redirect traffic to unintended destinations, potentially exposing sensitive information. Data center attacks also pose a significant risk, as vulnerabilities in routing protocols could be exploited to isolate a data center from the Internet, rendering its services inaccessible.
To address these blind spots in risk assessment, organizations must adopt a multi-pronged approach. Keeping an inventory of all devices connected to the network and the software running on them, including routing protocols, is crucial. This awareness enables organizations to identify vulnerabilities and prioritize their remediation efforts. Implementing segmentation strategies can also help protect unpatched devices from exposure to the Internet.
Additionally, software developers should prioritize security and reduce the likelihood of vulnerabilities in routing protocol implementations. Enhanced static and dynamic analysis techniques, as well as a secure software development lifecycle, can contribute to this. Effective communication channels should also be established to promptly address any identified vulnerabilities.
Vendors that integrate routing protocols into their devices become a potential source of third-party risk in the supply chain. Implementing software bills of materials (SBOMs) can provide greater visibility into the vulnerabilities present in devices and networks, enabling organizations to better manage their risks. Organizations must proactively assess their attack surface in cases where vendors do not provide the necessary transparency.
Furthermore, the security research community plays a crucial role in discovering and responsibly disclosing these vulnerabilities. Security researchers often provide more timely and effective remediation and mitigation recommendations compared to official security bulletins. For example, in the case of the recent BGP vulnerability, security researchers have developed an open-source BGP fuzzer that can quickly test protocol implementations to identify vulnerabilities.
Enhancing the security of routing protocols requires collaboration between software developers, vendors, and organizations. Security researchers can raise awareness of the potential risks associated with routing protocols and their broader impact on the ecosystem. However, organizations must prioritize a comprehensive understanding of their network devices, conduct vulnerability assessments, and establish effective threat detection and response mechanisms.
Ultimately, it is through the collective efforts of all stakeholders that the security of routing protocols can be strengthened, safeguarding the interconnected world we rely on.