TCP Invalid MSS Flood

Introduction:

The TCP Invalid MSS (Maximum Segment Size) Flood attack is a sophisticated form of Denial of Service (DoS) attack that exploits vulnerabilities in the TCP protocol's Maximum Segment Size parameter. This attack aims to overwhelm a target server or network by flooding it with TCP packets containing an invalid MSS value that falls outside the normal range of 536 to 65535. By exploiting this weakness, the attacker disrupts the server's ability to establish and manage legitimate TCP connections.

Understanding TCP Invalid MSS Flood Attacks:

In the TCP protocol, the Maximum Segment Size (MSS) parameter defines the largest amount of data that can be sent in a single TCP segment. A TCP Invalid MSS Flood attack involves sending an excessive volume of TCP packets with an invalid MSS value that is not within the standard range of 536 to 65535 bytes. These packets are often sent with forged or randomly generated source IP addresses to complicate detection and mitigation efforts.

During a TCP Invalid MSS Flood attack, the attacker aims to exploit the target server's handling of these malformed packets. The server allocates resources to process and analyze each incoming packet, including memory, CPU cycles, and network bandwidth. The overwhelming flood of packets with invalid MSS values consumes these resources rapidly, leading to performance degradation, service disruptions, and potential unavailability.

Implications of TCP Invalid MSS Flood Attacks:

TCP Invalid MSS Flood attacks can have severe implications for the targeted systems and networks:

• Denial of Service (DoS): The inundation of TCP packets with invalid MSS values overwhelms the victim server, causing it to exhaust resources and deny access to legitimate users. Critical services become unavailable, resulting in financial losses, user dissatisfaction, and reputational damage.

• Resource Exhaustion: TCP Invalid MSS Flood attacks deplete server resources, including memory, CPU cycles, and network capacity. The high volume of packets can destabilize the system, causing crashes, slowdowns, or even rendering the system unresponsive.

• Connection Instability: The flood of packets with invalid MSS values disrupts the proper establishment and maintenance of TCP connections. Legitimate connections may be disrupted, leading to connection instability, data loss, and the need for re-establishment.

How does the script deals with that:

• Blocking invalid MSS.