MAC Flooding Attack

Jan 22, 2021

MAC flooding is a method that can be used to impact the security protocols of different types of network switches. Essentially, MAC flooding inundates the network switch with data packets that disrupt the usual sender to recipient flow of data that is common with MAC addresses. The end result is that rather than data passing from a specific port or sender to a specific recipient, the data is blasted out across all ports.

MAC flooding inundates the network switch with data packets that disrupt the usual sender to recipient flow of data that is common with MAC addresses.

The basics of MAC flooding begin with a corruption of the translation table that is part of the function of the network switch. When functioning properly, the table will map each individual MAC address that is found on the network. Each MAC address is associated with a physical port on the network switch. This approach makes it possible to designate a specific and single point of termination for data sent across the network.

By flooding the switch with data packets, the translation table is thrown out of kilter and the connection between the ports and specific MAC addresses is destroyed. Instead, any data that is intended for a single MAC address is now sent out on all ports associated with the network. This means that any type of data that was intended for a single address is received by multiple addresses.

MAC (Media Access Control) Flooding is a type of cyber attack done in a network to compromise the security of the network switches. In this attack the network is flooded with the fake MAC addresses. The hacker uses this attack to steal sensitive data that is being transferred in the network. The attack is used for forcing the legitimate MAC table contents out of the switch and forcing the unicast flooding behavior for potentially sending sensitive information to portions of the network where it is not normally intended to go.

Procedure For The Attack

In this attack, the hacker first connects to the switch ports and floods it’s interface by forcing legitimate MAC addresses out of the MAC address table through very large number of fake MAC addresses .
Once the MAC address table is full, the network switch enters into the fail-open mode and behaves like a network hub, broadcasting all the packets on all the switch ports.
The hacker finally uses an packet analyzer to capture these packets to steal the sensitive information.

Image For Understanding The Attack

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Mitigation For The Attack

To stay safe from this attack, follow the following:

Authentication, Authorization, and Accounting Servers (AAA) can be used for authentication against MAC addresses as an preventive measures
Configure the switches to limit the number of MAC addresses on the ports that are connected to the end stations.

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OWASP TOP !0

Injection. Injection flaws, such as SQL, NoSQL, OS, and LDAP injection, occur when untrusted data is sent to an interpreter as part of a command or query. The attacker’s hostile data can trick the interpreter into executing unintended commands or accessing data without proper authorization. Broken Authentication. Application functions related to authentication and session management are often implemented incorrectly, allowing attackers to compromise passwords, keys, or session tokens, or to exploit other implementation flaws to assume other users’ identities temporarily or permanently. Sensitive Data Exposure. Many web applications and APIs do not properly protect sensitive data, such as financial, healthcare, and PII. Attackers may steal or modify such weakly protected data to conduct credit card fraud, identity theft, or other crimes. Sensitive data may be compromised without extra protection, such as encryption at rest or in transit, and requires special precautions when exchanged with the browser. XML External Entities (XXE). Many older or poorly configured XML processors evaluate external entity references within XML documents. External entities can be used to disclose internal files using the file URI handler, internal file shares, internal port scanning, remote code execution, and denial of service attacks. Broken Access Control. Restrictions on what authenticated users are allowed to do are often not properly enforced. Attackers can exploit these flaws to access unauthorized functionality and/or data, such as access other users’ accounts, view sensitive files, modify other users’ data, change access rights, etc. Security Misconfiguration. Security misconfiguration is the most commonly seen issue. This is commonly a result of insecure default configurations, incomplete or ad hoc configurations, open cloud storage, misconfigured HTTP headers, and verbose error messages containing sensitive information. Not only must all operating systems, frameworks, libraries, and applications be securely configured, but they must be patched/upgraded in a timely fashion. Cross-Site Scripting XSS. XSS flaws occur whenever an application includes untrusted data in a new web page without proper validation or escaping, or updates an existing web page with user-supplied data using a browser API that can create HTML or JavaScript. XSS allows attackers to execute scripts in the victim’s browser which can hijack user sessions, deface web sites, or redirect the user to malicious sites. Insecure Deserialization. Insecure deserialization often leads to remote code execution. Even if deserialization flaws do not result in remote code execution, they can be used to perform attacks, including replay attacks, injection attacks, and privilege escalation attacks. Using Components with Known Vulnerabilities. Components, such as libraries, frameworks, and other software modules, run with the same privileges as the application. If a vulnerable component is exploited, such an attack can facilitate serious data loss or server takeover. Applications and APIs using components with known vulnerabilities may undermine application defenses and enable various attacks and impacts. Insufficient Logging & Monitoring. Insufficient logging and monitoring, coupled with missing or ineffective integration with incident response, allows attackers to further attack systems, maintain persistence, pivot to more systems, and tamper, extract, or destroy data. Most breach studies show time to detect a breach is over 200 days, typically detected by external parties rather than internal processes or monitoring.

MAC Flooding Attack

Procedure For The Attack

Image For Understanding The Attack