A security protocol at the heart of most modern Wi-Fi devices, including computers, phones, and routers, has been broken, putting almost every wireless-enabled device at risk of attack.
The bug, known as "KRACK" for Key Reinstallation Attack, exposes a fundamental flaw in WPA2, a common protocol used in securing most modern wireless networks. Mathy Vanhoef, a computer security academic, who found the flaw, said the weakness lies in the protocol's four-way handshake, which securely allows new devices with a pre-shared password to join the network.
That weakness can, at its worst, allow an attacker to decrypt network traffic from a WPA2-enabled device, hijack connections, and inject content into the traffic stream.
In other words: this flaw, if exploited, gives an attacker a skeleton key to access any WPA2 network without a password. Once they're in, they can eavesdrop on your network traffic.
The bug represents a complete breakdown of the WPA2 protocol, for both personal and enterprise devices -- putting every supported device at risk.
"If your device supports Wi-Fi, it is most likely affected," said Vanhoef, on his website.
But because Vanhoef hasn't released any proof-of-concept exploit code, there's little risk of immediate or widespread attacks.
News of the vulnerability was later confirmed on Monday by US Homeland Security's cyber-emergency unit US-CERT, which about two months ago had confidentially warned vendors and experts of the bug, ZDNet has learned.
The warning came at around the time of the Black Hat security conference, when Vanhoef presented a talk on networking protocols, with a focus on the Wi-Fi handshake that authenticates a user joining a network.
The cyber-emergency unit has since reserved ten common vulnerabilities and exposures (CVE) records for the various vulnerabilities.
Cisco, Intel, Juniper, Samsung, and Toshiba are among the companies affected.
At its heart, the flaw is found in the cryptographic nonce, a randomly generated number that's used only once to prevent replay attacks, in which a hacker impersonates a user who was legitimately authenticated.
In this case, an attacker can trick a victim into reinstalling a key that's already in use. Reusing the nonce can allow an adversary to attack the encryption by replaying, decrypting, or forging packets.
Windows and latest versions of Apple's iOS are largely immune from the flaws, according to security researcher Kevin Beaumont, in a blog post.
However, Vanhoef said the security issue is "exceptionally devastating" for Android 6.0 Marshmallow and above.
via zdnet
