ARP Cache Poisoning

ARP Cache Poisoning [T1557.002]

Information

• Name: ARP Cache Poisoning

• ID: T1557.002

• Tactics: TA0006, TA0009

• Technique: T1557

Introduction

ARP Cache Poisoning, sub-technique T1557.002 within the MITRE ATT&CK framework, is a network-based attack aimed at manipulating the Address Resolution Protocol (ARP) cache of targeted hosts. Attackers exploit ARP's lack of authentication by injecting forged ARP messages into a local network. This manipulation redirects network traffic, enabling attackers to intercept, modify, or disrupt communications between legitimate hosts.

Deep Dive Into Technique

ARP Cache Poisoning targets the ARP protocol, which resolves IP addresses to MAC addresses within a local subnet. Due to ARP's stateless and trusting nature, attackers can easily exploit it by sending fraudulent ARP reply packets.

Technical execution typically involves:

• ARP Spoofing Tools: Attackers commonly use tools such as Ettercap, Cain & Abel, arpspoof, and BetterCAP to automate ARP poisoning attacks.

• Forged ARP Packets: The attacker sends unsolicited ARP replies to hosts on the network, falsely associating their MAC address with the IP address of another host, usually the default gateway or critical servers.

• Man-in-the-Middle (MitM) Positioning: By poisoning ARP caches, attackers position themselves as intermediaries, allowing them to intercept, monitor, or modify network traffic.

• Session Hijacking and Credential Theft: Once positioned as a MitM, attackers can capture sensitive data such as usernames, passwords, session cookies, and other confidential information.

• Denial of Service (DoS): Attackers may disrupt network communication by redirecting traffic to non-existent MAC addresses or by creating loops, causing network disruptions and outages.

Mechanisms involved include:

• ARP Cache Manipulation: Injecting fake ARP replies into victim hosts' ARP tables.

• Continuous ARP Flooding: Periodically sending spoofed ARP packets to keep the victim's ARP cache poisoned.

• MAC Address Spoofing: Attackers may spoof MAC addresses to evade detection or to impersonate legitimate network devices.

When this Technique is Usually Used

ARP Cache Poisoning typically appears in various attack scenarios and stages, including:

• Initial Reconnaissance and Network Discovery: Attackers use ARP poisoning to intercept traffic and identify sensitive hosts, services, and credentials.

• Credential Theft and Data Exfiltration: Attackers position themselves as MitM to capture login credentials, session tokens, and sensitive data.

• Privilege Escalation and Lateral Movement: Attackers intercept and modify network communications to exploit vulnerabilities or escalate privileges across hosts.

• Denial of Service Attacks: Attackers disrupt network availability by redirecting or dropping packets, causing service outages.

• Internal Network Penetration Testing: Security professionals and penetration testers use ARP poisoning techniques to evaluate network security posture and identify vulnerabilities.

How this Technique is Usually Detected

Detection methods and indicators include:

• Network Traffic Analysis:

  • Unusual ARP traffic patterns, such as frequent or unsolicited ARP replies.

  • Multiple IP addresses associated with a single MAC address.

  • Frequent ARP cache updates or anomalies in ARP tables.

• Intrusion Detection and Prevention Systems (IDS/IPS):

  • Tools like Snort, Suricata, and Zeek can detect anomalies in ARP traffic.

  • Signature-based detection rules specifically targeting ARP spoofing attempts.

• ARP Monitoring Tools:

  • Specialized tools such as ARPwatch, XArp, and ARP Guard monitor ARP cache changes and alert administrators of suspicious activities.

• Endpoint Detection and Response (EDR) Solutions:

  • Detect suspicious ARP cache modifications on endpoints.

  • Monitor and log ARP table changes for forensic analysis.

Indicators of Compromise (IoCs):

• Unrecognized MAC addresses appearing in ARP caches.

• Frequent ARP cache updates or flapping MAC-IP mappings.

• Sudden network traffic redirections or unexpected latency increases.

• Detection of known ARP poisoning tools (e.g., Ettercap, BetterCAP) on endpoints.

Why it is Important to Detect This Technique

Detecting ARP Cache Poisoning is critical due to its significant impacts on network security and integrity:

• Confidentiality Breach:

  • Attackers intercept sensitive data, leading to data leakage, credential theft, or intellectual property compromise.

• Integrity Impact:

  • Attackers may modify intercepted data, injecting malicious payloads or misinformation into legitimate communications.

• Availability Disruption:

  • ARP poisoning can cause denial-of-service conditions, disrupting critical network services and impacting business continuity.

• Lateral Movement Facilitation:

  • Attackers leverage ARP poisoning to pivot within internal networks, escalating privileges and compromising additional hosts.

• Compliance and Regulatory Risks:

  • Failure to detect and respond to ARP poisoning attacks can result in compliance violations, legal consequences, and damage to organizational reputation.

Early detection significantly reduces the attacker's window of opportunity, enabling rapid response, containment, and mitigation of potential damages.

Examples

Real-world examples highlighting ARP Cache Poisoning scenarios, tools, and impacts include:

• Ettercap-based Credential Theft:

  • Attack Scenario: Attackers deploy Ettercap in ARP poisoning mode to intercept HTTP and FTP traffic within a corporate LAN.

  • Tools Used: Ettercap, Wireshark.

  • Impact: Attackers successfully capture login credentials, enabling unauthorized access to internal resources.

• Cain & Abel ARP Poisoning Attack:

  • Attack Scenario: An attacker uses Cain & Abel to perform ARP poisoning on a local network, intercepting sensitive email communications.

  • Tools Used: Cain & Abel, Wireshark.

  • Impact: Confidential emails intercepted, leading to privacy breaches and potential intellectual property theft.

• BetterCAP Network Redirection Attack:

  • Attack Scenario: Attackers utilize BetterCAP to redirect internal network traffic through their machine, injecting malicious payloads into downloaded files.

  • Tools Used: BetterCAP, Metasploit.

  • Impact: Distribution of malware across multiple endpoints, resulting in compromised systems and data exfiltration.

• Internal Penetration Testing:

  • Attack Scenario: Security teams perform ARP poisoning using arpspoof to assess internal network vulnerabilities and identify insecure protocols in use.

  • Tools Used: arpspoof, ARPwatch, Wireshark.

  • Impact: Identification of vulnerable network configurations, enabling proactive security enhancements and improved security posture.