Penchuk Cyber Blog

A POST Flood Attack is a type of Distributed Denial of Service (DDoS) attack that targets the application layer (Layer 7 of the OSI model) by sending an overwhelming number of HTTP POST requests to a web server. Unlike traditional volumetric attacks that consume bandwidth, this method is designed to exhaust server resources such as CPU, memory, or application-specific processes. This form of attack is particularly insidious because it mimics legitimate traffic, making it difficult to detect using conventional anomaly detection systems or rate-limiting protections. Attack Methodology Connection Initiation : The attacker initiates multiple HTTP sessions, often via botnets or tools like LOIC, HOIC, or custom scripts. POST Request Flooding : Each session sends numerous HTTP POST requests with large payloads or incomplete data , often designed to keep the connection open for as long as possible. Server Exhaustion : Because POST requests typically require more server processing...

Class: Applicative Category: Layer 7 (Application Layer) DDoS Alternative Names: Slow HTTP POST, R-U-Dead-Yet (RUDY) A Slow POST attack is a type of application-layer DDoS attack that exploits the way web servers handle HTTP POST requests. Instead of overwhelming a server with a flood of requests, this attack operates by sending a legitimate-looking HTTP POST request with a declared large content length —but transmitting the actual body of the request extremely slowly , often byte by byte. The goal is to tie up server resources , keeping connections open for as long as possible. Since many web servers allocate memory and processing resources per open connection, a small number of Slow POST requests can exhaust available server threads or connection pools—leading to service degradation or complete unavailability. Attack Mechanism The attacker sends a valid HTTP POST request header with a large Content-Length value (e.g., Content-Length: 1000000 ). The body of the reques...

A Login Flood is a type of application-layer Denial of Service (DDoS) attack where an attacker sends a high volume of login requests to a target’s authentication endpoint. This is typically done to exhaust system resources, degrade performance, or cause total unavailability of the login service. Unlike brute force attacks that aim to gain unauthorized access, the goal of a login flood is disruption, not access. Attack Vector Login Flood attacks are usually executed via automated scripts or botnets that: Rapidly send repeated HTTP POST requests to the login endpoint (e.g., /login , /auth , /signin ) Include either random, valid, or dictionary-based usernames and passwords Often bypass simple rate-limiting by rotating IP addresses, user agents, or using proxy networks (e.g., TOR, VPNs) Impact Authentication Service Disruption : Legitimate users may experience slowdowns or inability to log in. Resource Exhaustion : CPU, memory, and database resources can be overwhelmed b...