When we talk about Wifi security, the precautions are never too many.
Especially when, just recently, there was talk of a significant vulnerability right in the Wifi security area, called Kr00k.
First of all, the need to have a safe connection is fundamental, whether if you deal with a private net or with an internal net of a company.
The trtaditional nets with wires, having a physical substance, assure greater guarantees of protection despite external attacks. Indeed, it’s impossible for an unknown third party to listen, to read conversations or acquire personal info without having a direct and physical access to the lines, which pass through the walls of the building.
Moreover, we can’t deny that the wireless connections, so the ones without any wire, such as the Wifi nets, appear to be more comfortable and practical, even if, unfortunately, they expose to major risks the security of their own connection. In this case, indeed, the vector of the transmission is a blank space, not a physical wire, and the coverage area depends on the power of the signal, not on the lenght of the wire.
So, it’s a device that send the info from the intern of the local wireless net and to which a third unknown person can easily access, by using a simple receiving device that is withing the range of the signal sent by the wireless device.
That’s why it is important to protect our own Wifi net in an efficient way, in order to communicate without any risk.
Wifi security: setup of the wireless access point
Il Wireless Access Point is a router controller of the net and it’s fundamental for the safety of a Wifi, because the settings used for the hardware component are crucial in order to prevent an external attack from succeeding.
How to setup correctly our wireless access point? Here are the steps to follow:
- create a personal access as an admin: it’s necessary to activate the firmwares, that show a user intrerface on the browser just when the IP address is recalled from the access point; the access is with an admin account, which has a user name and standard password, not individual, but the same for all the devices of the same model and, therfore, simple, such as “admin” and “1234”. Indeed, at the beginning of the setup, personalised data must be allocated to the admin account;
- choose WPA2 as the decryption proceedure: the WPA and WEP setup protocols are obsolete and more dangerous; it’s recommended to consider net devices that support WPA2;
- choose a safe password for the Wifi;
- use a net name that’s unidentifiable: create a SSID, which means Service Set Identifiers that’s not due to somebody in particular; this defines your net and it’s shown on any device that’s within the range of the net signal, so avoid to indicate personal data that indentifies you, your location or your company, except if you run a public hotspot; to hide the name of the wireless connection with a hidden SSID is not a great idea, besides, because the hackers easily get around obstacles and, by contrast, it gets more difficult for the legit clients to get a conncetion with the net;
- activate the automatic update of the firmware: the firmware of the wireless access point has to be updated to the most recent version, in order to avoid that the hackers find flaws in the security and exploit them, maybe to obtain the admin rights or to download harmful softwares.
Kr00k vulnerability: risk of interception for the Wifi devices
The flaw in the security of the Wifi chip that risks to encourage attacks from long distance, interceptions and unencrypted network traffic with WPA2 protocol has been called Kr00k.
The discovered vulnerability put at risk billions of wireless devices, even if it already exists the patch for many f them.
In other words, the sensitive data transmitted by the users through wireless nets have been put in serious danger.
The Kr00k vulnerability concerns the Wifi chips produced by Broadcom and Cypress, that are found in many devices, such as:
- Amazon Echo, second generation;
- Amazon Kindle, eight generation;
- Apple iPad mini 2;
- Apple iPhone 6, 6S, 8, XR;
- Apple MacBook Air Retina 13”, 2018;
- Google Nexus 5;
- Google Nexus 6;
- Google Nexus 6S;
- Raspberry Pi 3;
- Samsung Galaxy S4 GT-I9505;
- Samsung Galaxy S8;
- Xiaomi Redmi 3S.
But the flaw could attack as well some other models od Access Point and router, such as:
- Asus RT-N12;
- Huawei B612S-25d;
- Huawei EchoLife HG8245H;
- Huawei E5577Cs-321.
The name of the flaw, Kr00k, comes from the famous attack technique KRACK (Key Reinstallation AttaCK), discovered in 2017, that allwed to get around the encryption of the WPA2 protocol.
Even not having the same level of danger of the KRACK technique, this new vulnerability is anyway capable of putting at risk of interception billions of devices.
The exploit of Kr00k consists on the reinstallation of an encryption key and it can occur when it loses the connection to the Access Point, because of an interference or a sudden shut down of the device, or because of the weakness of the signal.
When this happens, the WPA2 protocol is projected to continue the transmission of some of the data that it was already sending with a protected buffer through an encryption key composed by a sequence of zeros only.
That’s why, somebody that wants to carry out an attack can intercept this portion of network traffic and crack it, decrypting the data that are transmitted, just by knowing the encryption key.
Anyway, we’re talking about just a few kilobytes of data, but there’s always the possibility to intercept a quantity of sensitive and confidential data.
After the discover of the flaw, the ESET reaserchers have informed the producers of the devices exposed to the Kr00k, and Apple and Amazon have already released a patch to correct the flaw for their devices, while the other producers are still working on the updating.
In order to reduce the risk of a cyber attack that exploits the Kr00k flaw, the advice is to update your Wifi device and to activate the WPA3 authentication system on the Access Point, because this version would be immune to the flaw.
Another way to reduce the Wifi safety risks is to rely on the encrypted systems for your communications, like Crypty Talk, in order to stay away from potential interceptions and to not expose your own sensitive data to external attacks.