Today, most modern enterprise networks afford some type of remote access to a wide variety of different groups – employees, contractors, partners, vendors, and even customers, in some cases. Remote access has always been fraught with a plethora of major issues, including:
- Endpoint security: When a remote endpoint joins the network, any attacks originating from that endpoint are potentially able to infiltrate the internal network.
- User privileges: Creating granular access control strategies for a wide variety of different remote users and groups is immensely challenging. In many cases, this has, unfortunately, led to overallocation of privileges (sometimes due to admins taking shortcuts or not having enough time, and also sometimes due to lack of understanding or misconfiguration). This can easily lead to either accidentally or deliberately harmful activity on the part of connected end users.
- Malware infections: Malware infections on remotely-connected systems can access internal resources, which could potentially allow access to sensitive data or additional targets.
- Weak storage of credentials: Many organizations still have inadequate credential security practices in place—from relying on manual recording of passwords, using weak encryption, and more. Attackers who find or compromise credentials could potentially use them to remotely access network or application resources, especially without multifactor authentication and other strong password security measures in place.
- Monitoring: Monitoring remote user and system events is critical to keeping pace with potential attacks, but many enterprises have difficulty in readily tracking and proving who is doing what.
IT Supply Chain Cybersecurity Risks
The remote access challenge is even more complicated when considered as part of a supply chain. Sophisticated attackers are willing to use any means necessary to gain access to sensitive data, and third-party suppliers and vendors may have fewer security controls in place, making them easier targets of an initial attack.
Once breached, attackers can leverage your vendors’ remote access as an ingress point into your environment. There have been numerous examples of this type of illicit activity in the past few years, but it was the 2013 Target breach that really opened our eyes to this risk. In late 2013, Target experienced a significant breach of roughly 110 million customers’ data, with at least 40 million payment cards stolen .
During the course of the investigation, it was found that Target was initially breached through a connection established by one of their HVAC vendor, Fazio Mechanical Services. The attackers stole network credentials from Fazio and then used these to successfully access the Target network, ultimately stealing staggering quantities of data over several months. This exact same kind of privileged remote access breach has happened time and time again since then, and the issues are always somewhere at the intersection of remote access and privileged account misuse.
Technology solutions for mitigating remote access risk should include privilege management. Privileged user monitoring is a large part of Carnegie Mellon Computer Emergency Response Team’s (CERT) recommendations for prevention of insider threats and for compliance reporting of administrator actions. Some of the mechanisms to prevent privileged insider abuse highlighted by CERT include the following:
- Enforce separation of duties, separation of privilege, and least privilege.
- Implement strict password and account-management policies and practices.
- Log, monitor, and audit employee online actions.
- Exercise extra caution and oversight with system administrators and privileged users.
Organizations also need a policy and approach to managing and monitoring privileged users who have remote access into the network. By examining the levels of access needed to perform most daily activities and crafting policy that supports these job functions, while still maintaining separation of duties and the principle of least privilege, organizations are getting off to a good start. Processes for granting access should be in place and in line with the privileged user policies. Periodic audits should also be a part of the program. While all of these concepts are easy to grasp, putting them into practice can be extremely challenging without technologies that automate and streamline these efforts.
- Examples of remote access gone terribly wrong!
- How to evaluate your remote access strategy and infrastructure
- Specific security controls and practices that could improve remote access models in your environment
Dave Shackleford, Cybersecurity Expert and Founder of Voodoo Security
Dave Shackleford is the owner and principal consultant of Voodoo Security and a SANS analyst, senior instructor, and course author. He has consulted with hundreds of organizations in the areas of security, regulatory compliance, and network architecture and engineering, and is a VMware vExpert with extensive experience designing and configuring secure virtualized infrastructures. He has previously worked as CSO for Configuresoft, CTO for the Center for Internet Security, and as a security architect, analyst, and manager for several Fortune 500 companies.