Best Practices for Securing Wireless Networks
Most organizations employ mobile computing, which utilizes wireless communications for staff members to perform day-to-day tasks with more ease.
While some organizations have deployed enterprise security standards on their wireless networks, Trustwave SpiderLabs has observed some organizations deviating from security best practices when it comes to managing a wireless environment leaving these wireless networks as low-hanging fruit for attackers to abuse.
How Does One Attack Corporate Wireless Network?
How a threat actor conducts such an attack depends on how the organization has configured its wireless network. Unfortunately, Trustwave SpiderLabs, in many cases, has observed organizations making it easy for an attacker by misconfiguring their wireless setup. These errors include using a guest portal for a corporate wireless network, configurations using encryption standards (WPA-PSK, WPA2-PSK or WPA3-PSK) based authentication and RADIUS authentication without certificate validation. When organizations use these configurations, it becomes an easy target for any competent attacker.
For example, an attacker can bypass a guest portal by simply sniffing for MAC addresses which have been authenticated to the wireless network; once the attacker obtains an authenticated MAC address and spoofs it, they can gain access to the wireless network.
WPA-PSK attacks would depend on the password's complexity and the rotation of the password, especially after an employee leaves the organization. If the password is weak, attackers will be able to recover the password by cracking the WPA hash and authenticating it to the wireless network. Even with MAC address filtering in place, knowledgeable attackers would be able to sniff for devices that have been authenticated to the wireless network and spoof the MAC address to bypass the additional layer.
RADIUS authentication without validation of certificate can be exploited using "Evil-Twin attacks", resulting in the attacker gaining access to the corporate account and the corporate network, allowing them to move laterally on the network until the objective is obtained.
Attacks become even more successful when the wireless network is considered a trusted network and doesn't prompt for Multi-Factor Authentication (MFA). This configuration could allow attackers to gain access to corporate email accounts, depending on the user's role, and then to sensitive data stored in the cloud.
How Do We Secure Wireless Networks?
Most wireless vendors provide monitoring features to detect wireless spoofing, deauthentication, and other types of attacks. Proper security protocols recommend that these security features be enabled to detect and alert security teams to respond to such attacks.
Having additional layers of security, such as segregation and segmentation of different wireless profiles from the corporate network, can help deter sensitive corporate information from being accessed. Guest networks should never be able to access corporate networks, and it is vital that segregation checks are performed to ensure configurations are properly implemented. Conversely, corporate devices should never be allowed to connect to guest networks.
Wireless corporate networks should always be configured with Enterprise Grade Security, ensuring 802.1X is implemented properly and organizations should remove older, unused wireless configurations. Additionally, employing a Zero-Trust approach is highly recommended.
Scope of a Wireless Assessment?
All wireless networks should be in scope for a wireless assessment, especially those wireless networks that use a single controller. Additionally, corporate devices should also be included, to review the wireless configuration profile and previously connected wireless networks.
How can Trustwave SpiderLabs help?
Trustwave's elite security team, SpiderLabs, can scope and execute thorough testing of the environment with their deep, specialized knowledge and provide recommendations to strengthen the security posture.
For more information on Trustwave SpiderLabs Wireless Penetration Testing and Penetration Testing services, please read SpiderLabs Wireless Penetration Test.
