Don’t you just hate security flaws? WPA2 is the security protocol for a wide range of WiFi systems but it is also known to pose a security flaw that allows cyber criminals to steal sensitive data including passwords, credit card numbers, and even emails. Depending on the network configuration of the WiFi system, attackers can also manipulate or inject malicious information into the system. Ransomware is a popular weapon of choice for those cyber criminals.
Understanding the Severity of the WPA2 Flaw
To give you a quick overview on the situation, a range of vulnerabilities was found in Linksys, MediaTek, OpenBSD, Windows, Apple, Linux, and Android. As a proof on concept, researchers rolled out a key reinstallation attack (or KRACK) against a specimen Android smartphone. This attack was executed with the knowledge that Linux and Android 6.0 or higher were particularly vulnerable. Results showed that the attackers could trick both operating systems into reinstalling the all-zero encryption key.
The key attack targeted the four-way handshake of the WPA2 protocol. A handshake is initiated when a user signals that his or her intentions to join a protected WiFi network. The WPA2 protocol is called to verify that the access point and client have the correct credentials. Next, the attacker replays and manipulates the cryptographic handshake message. This means that both the receive packet number and incremental transmit packet number are reset to their initial values, after the victim reinstalls the key. Once the attackers rebroadcast the initial handshake, they can intercept the rest of the conversation.
How Should You Respond to Potential Threats?
- Update regularly: A quick way to fix the problem is to update affected products as soon as patches become available. For example, Microsoft released security updates within a week after the flaw was discovered. If the users enabled automatic Windows Update, then you are protected.
- Install all recommended updates: You should never ignore any recommended updates from your network equipment manufacturers and the end device.
- Test your system with a vulnerability detection tool: You will not know what next steps to take until you uncover every potential loophole in your systems. Today’s cyber attacks can affect wireless infrastructure devices in the form of supplicants and authenticators. Depending on your device configuration, attackers can exploit its vulnerabilities by decrypting wireless packets, performing packet relaying, and potentially inject or forge packets into a WiFi network.
Although fundamental flaws (e.g. KRACK) that impact everyday web users are exceptionally rare, they are not unprecedented. That’s why you should never let your guard down. The WPA2 flaw is just one of the many flaws that exist in the cyber world. In 2014, there was the Heartbleed vulnerability, which caused a widespread impact across the spectrum.
One of the misconceptions that many enterprises have is that they believe VPNs and TLS (HTTPS) are the ones that provide true protection, even if a WiFi network is wide open. This is possibly the reason why the flaw disclosure was taken with a pinch of salt until things go wrong.