"the group temporal key (GTK) that is shared among all authorized clients in a WPA2 network. In the standard behavior, only an AP is supposed to transmit group-addressed data traffic encrypted using the GTK and clients are supposed to decrypt that traffic using the GTK. However, nothing in the standard stops a malicious authorized client from injecting spoofed GTK-encrypted packets! Exploiting the vulnerability, an insider (authorized user) can sniff and decrypt data from other authorized users as well as scan their Wi-Fi devices for vulnerabilities, install malware and possibly compromise those devices.
In short, this vulnerability means that inter-user data privacy among authorized users is inherently absent over the air in a WPA2-secured network. "
In 2016 it was shown that the WPA and WPA2 standards contain an insecure expository random number generator (RNG). Researchers showed that, if vendors implement the proposed RNG, an attacker is able to predict the group key (GTK) that is supposed to be randomly generated by the access point (AP). Additionally, they showed that possession of the GTK enables the attacker to inject any traffic into the network, and allowed the attacker to decrypt unicast internet traffic transmitted over the wireless network. They demonstrated their attack against an Asus RT-AC51U router that uses the MediaTek out-of-tree drivers, which generate the GTK themselves, and showed the GTK can be recovered within two minutes or less. Similarly, they demonstrated the keys generated by Broadcom access daemons running on VxWorks 5 and later can be recovered in four minutes or less, which affects, for example, certain versions of Linksys WRT54G and certain Apple AirPort Extreme models. Vendors can defend against this attack by using a secure RNG. By doing so, Hostapd running on Linux kernels is not vulnerable against this attack and thus routers running typical OpenWrt or LEDE installations do not exhibit this issue.[54] "
believed to affect all variants of WPA and WPA2; however, the security implications vary between implementations, depending upon how individual developers interpreted a poorly specified part of the standard. Software patches can resolve the vulnerability but are not available for all devices.[57] KRACK exploits a weakness in the WPA2 4-Way Handshake, a critical process for generating encryption keys. Attackers can force multiple handshakes, manipulating key resets. By intercepting the handshake, they could decrypt network traffic without cracking encryption directly. This poses a risk, especially with sensitive data transmission.[58]"
Here’s the summary for the wikipedia article you mentioned in your comment:
KRACK ("Key Reinstallation Attack") is a replay attack (a type of exploitable flaw) on the Wi-Fi Protected Access protocol that secures Wi-Fi connections. It was discovered in2016by the Belgian researchers Mathy Vanhoef and Frank Piessens of the University of Leuven. Vanhoef's research group published details of the attack in October 2017. By repeatedly resetting the nonce transmitted in the third step of the WPA2 handshake, an attacker can gradually match encrypted packets seen before and learn the full keychain used to encrypt the traffic. The weakness is exhibited in the Wi-Fi standard itself, and not due to errors in the implementation of a sound standard by individual products or implementations. Therefore, any correct implementation of WPA2 is likely to be vulnerable. The vulnerability affects all major software platforms, including Microsoft Windows, macOS, iOS, Android, Linux, OpenBSD and others.The widely used open-source implementation wpa_supplicant, utilized by Linux and Android, was especially susceptible as it can be manipulated to install an all-zeros encryption key, effectively nullifying WPA2 protection in a man-in-the-middle attack. Version 2.7 fixed this vulnerability.The security protocol protecting many Wi-Fi devices can essentially be bypassed, potentially allowing an attacker to intercept sent and received data.
What do you mean? Wifi is already secured.
no both options are fundamentally insecure. the current standard 2 and the version 3 of wpa
ahh, i see what you are saying. You aren’t saying that WiFi is not secured, you are saying the security has been compromised.
https://web.archive.org/web/20151113152528/http://www.airtightnetworks.com/WPA2-Hole196
"the group temporal key (GTK) that is shared among all authorized clients in a WPA2 network. In the standard behavior, only an AP is supposed to transmit group-addressed data traffic encrypted using the GTK and clients are supposed to decrypt that traffic using the GTK. However, nothing in the standard stops a malicious authorized client from injecting spoofed GTK-encrypted packets! Exploiting the vulnerability, an insider (authorized user) can sniff and decrypt data from other authorized users as well as scan their Wi-Fi devices for vulnerabilities, install malware and possibly compromise those devices.
In short, this vulnerability means that inter-user data privacy among authorized users is inherently absent over the air in a WPA2-secured network. "
https://en.wikipedia.org/wiki/Wi-Fi_Protected_Access#Security_issues
" Predictable Group Temporal Key (GTK)
In 2016 it was shown that the WPA and WPA2 standards contain an insecure expository random number generator (RNG). Researchers showed that, if vendors implement the proposed RNG, an attacker is able to predict the group key (GTK) that is supposed to be randomly generated by the access point (AP). Additionally, they showed that possession of the GTK enables the attacker to inject any traffic into the network, and allowed the attacker to decrypt unicast internet traffic transmitted over the wireless network. They demonstrated their attack against an Asus RT-AC51U router that uses the MediaTek out-of-tree drivers, which generate the GTK themselves, and showed the GTK can be recovered within two minutes or less. Similarly, they demonstrated the keys generated by Broadcom access daemons running on VxWorks 5 and later can be recovered in four minutes or less, which affects, for example, certain versions of Linksys WRT54G and certain Apple AirPort Extreme models. Vendors can defend against this attack by using a secure RNG. By doing so, Hostapd running on Linux kernels is not vulnerable against this attack and thus routers running typical OpenWrt or LEDE installations do not exhibit this issue.[54] "
https://en.wikipedia.org/wiki/KRACK " The KRACK attack
believed to affect all variants of WPA and WPA2; however, the security implications vary between implementations, depending upon how individual developers interpreted a poorly specified part of the standard. Software patches can resolve the vulnerability but are not available for all devices.[57] KRACK exploits a weakness in the WPA2 4-Way Handshake, a critical process for generating encryption keys. Attackers can force multiple handshakes, manipulating key resets. By intercepting the handshake, they could decrypt network traffic without cracking encryption directly. This poses a risk, especially with sensitive data transmission.[58]"
Here’s the summary for the wikipedia article you mentioned in your comment:
KRACK ("Key Reinstallation Attack") is a replay attack (a type of exploitable flaw) on the Wi-Fi Protected Access protocol that secures Wi-Fi connections. It was discovered in 2016 by the Belgian researchers Mathy Vanhoef and Frank Piessens of the University of Leuven. Vanhoef's research group published details of the attack in October 2017. By repeatedly resetting the nonce transmitted in the third step of the WPA2 handshake, an attacker can gradually match encrypted packets seen before and learn the full keychain used to encrypt the traffic. The weakness is exhibited in the Wi-Fi standard itself, and not due to errors in the implementation of a sound standard by individual products or implementations. Therefore, any correct implementation of WPA2 is likely to be vulnerable. The vulnerability affects all major software platforms, including Microsoft Windows, macOS, iOS, Android, Linux, OpenBSD and others.The widely used open-source implementation wpa_supplicant, utilized by Linux and Android, was especially susceptible as it can be manipulated to install an all-zeros encryption key, effectively nullifying WPA2 protection in a man-in-the-middle attack. Version 2.7 fixed this vulnerability.The security protocol protecting many Wi-Fi devices can essentially be bypassed, potentially allowing an attacker to intercept sent and received data.to opt out, pm me ‘optout’. article | about