Query: EDR alert: possible ARP Cache Poisoning (T1557.002)
Matching passage: T1557.002 ARP Cache Poisoning. Tactics: credential access, collection. Description: Adversaries may poison Address Resolution Protocol (ARP) caches to position themselves between the communication of two or more networked devices. This activity may be used to enable follow-on behaviors such as [Network Sniffing](https://attack.mitre.org/techniques/T1040) or [Transmitted Data Manipulation](https://attack.mitre.org/techniques/T1565/002). The ARP protocol is used to resolve IPv4 addresses to link layer addresses, such as a media access control (MAC) address.(Citation: RFC826 ARP) Devices in a local network segment communicate with each other by using link layer addresses. If a networked device does not have the link layer address of a particular networked device, it may send out a broadcast ARP request to the local network to translate the IP address to a MAC address. The device with the associated IP address directly replies with its MAC address. The networked device that made the ARP request will then use as well as store that information in its ARP cache. An adversary may passively wait for an ARP request to poison the ARP cache of the requesting device. The adversary may reply with their MAC address, thus deceiving the victim by making them believe that they are communicating with the intended networked device. For the adversary to poison the ARP cache, their reply must be faster than the one made by the legitimate IP address owner. Adversaries may also send a gratuitous ARP reply that maliciously announces the ownership of a particular IP address to all the devices in the local network segment. The ARP protocol is stateless and does not require authentication. Therefore, devices may wrongly add or update the MAC address of the IP address in their ARP cache.(Citation: Sans ARP Spoofing Aug 2003)(Citation: Cylance Cleaver) Adversaries may use ARP cache poisoning as a means to intercept network traffic. This activity may be used to collect and/or relay data such as credentials, especially those sent over an insecure, unencrypted protocol.(Citation:
Near-miss passage: T1557.004 Evil Twin. Tactics: credential access, collection. Description: Adversaries may host seemingly genuine Wi-Fi access points to deceive users into connecting to malicious networks as a way of supporting follow-on behaviors such as [Network Sniffing](https://attack.mitre.org/techniques/T1040), [Transmitted Data Manipulation](https://attack.mitre.org/techniques/T1565/002), or [Input Capture](https://attack.mitre.org/techniques/T1056).(Citation: Australia ‘Evil Twin’) By using a Service Set Identifier (SSID) of a legitimate Wi-Fi network, fraudulent Wi-Fi access points may trick devices or users into connecting to malicious Wi-Fi networks.(Citation: Kaspersky evil twin)(Citation: medium evil twin) Adversaries may provide a stronger signal strength or block access to Wi-Fi access points to coerce or entice victim devices into connecting to malicious networks.(Citation: specter ops evil twin) A Wi-Fi Pineapple – a network security auditing and penetration testing tool – may be deployed in Evil Twin attacks for ease of use and broader range. Custom certificates may be used in an attempt to intercept HTTPS traffic. Similarly, adversaries may also listen for client devices sending probe requests for known or previously connected networks (Preferred Network Lists or PNLs). When a malicious access point receives a probe request, adversaries can respond with the same SSID to imitate the trusted, known network.(Citation: specter ops evil twin) Victim devices are led to believe the responding access point is from their PNL and initiate a connection to the fraudulent network. Upon logging into the malicious Wi-Fi access point, a user may be directed to a fake login page or captive portal webpage to capture the victim’s credentials. Once a user is logged into the fraudulent Wi-Fi network, the adversary may able to monitor network activity, manipulate data, or steal additional credentials. Locations with high concentrations of public Wi-Fi access, such as airports, coffee shops, or libraries, may be targets for adversaries to set up illegitimate