WPA2 WiFI security protocol breached, experts warn

Vanhoef said that the attack exploits the four-way handshake that is used to establish a key for encrypting traffic. The vulnerability affects a number of operating systems and devices, Vanhoef says, including Android, Linux, Apple, Windows, OpenBSD, MediaTek, Linksys and others. Android 6.0 Marshmallow and later, and Linux kernel 2.4 and later, are especially hard-hit. To implement KRACKs the hacker needs to be within the physical range of the Wi-Fi router. In the meantime you can mitigate attacks by connecting to internet resources over secure protocols such as HTTPS and SSL.

The vulnerability poses a big problem for businesses who operate local wi-fi networks and assume they are trusted environments; enterprises with authentication-free network resources, as an example, are specifically at greater risk.

However, any web traffic that was not encrypted would be easily visible to the attacker – including traffic within local Wi-Fi networks. Multiple vendors have already issued patches to fix the issues. The organisation CERT/CC also disseminated news of the vulnerability to vendors on 28th August so at this stage its unlikely your router manufacturer has not received the news.

The security issue was discovered by Mathy Vanhoef at the Katholieke Universiteit Leuven in Belgium.

The solution to this problem is to immediately update the device as soon as a security patch becomes available. “Therefore, any correct implementation of WPA2 is likely affected”.

The flaw is also present in the earlier, WPA security protocol, and with any encryption suite, including WPA-TKIP, AES-CCMP, and GCMP. Rather, it’s in the implementation.

In other words, there’s probably no need to turn off your router and disable Wi-Fi on all your devices, at least not yet.

When connecting to WiFi, the presence of WPA2 is often indicated by a lock next to a WiFi icon, as in this screenshot of an Android device. “After all, these protocols are explicitly created to process retransmitted frames, and are possibly reinstalling keys while doing so”, said the team.

Vanhoef has published his findings in a detailed research paper, Key Reinstallation Attacks: Forcing Nonce Reuse in WPA2. Though it’s not yet clear, the re-use of a non-random key could allow an attacker to piggyback their way into a wireless network and then snoop on the data being transmitted within. In such cases, the encryption between the router and client device will be completely broken. The researchers point out that this will “not work on a properly configured HTTPS site”, but will work on a “significant fraction” that are poorly set up. You should contact any company whose services you use and ask if the connection is secured using TLS 1.2, and if so your connection with that service is safe for now. Vanhoef manages to steal the user’s Match.com password and username. He points out that the attack is not only limited to recovering login credentials (i.e. e-mail addresses and passwords).

One thing that users may do is use VPN connections to use an extra layer of protection so that attackers can not decrypt the traffic even if they attack a device successfully.

Depending on the network configuration, attackers can inject ransomware or other malware into websites. Vanhoef noted that Windows and iOS are less affected because they do not accept one-time keys that have been sent a few times. “However, we show that the 4-way handshake is vulnerable to a key reinstallation attack”.

However, it may be hard to update some older Wi-Fi routers.