attack-tree.md

Attack Tree Analysis for valyala/fasthttp

Objective: To compromise an application using fasthttp by exploiting vulnerabilities in fasthttp's request/response handling, memory management, or protocol implementation, leading to unauthorized access, data breaches, denial of service, or code execution within the application's context.

Attack Tree Visualization

Attack Goal: Compromise fasthttp Application [CRITICAL NODE] ├───[AND] Exploit fasthttp Vulnerabilities [CRITICAL NODE] │ ├───[OR] Request Handling Vulnerabilities [CRITICAL NODE, HIGH-RISK PATH] │ │ ├─── HTTP Request Smuggling [CRITICAL NODE, HIGH-RISK PATH] │ │ │ ├───[AND] Parsing Inconsistencies [HIGH-RISK PATH] │ │ │ │ ├─── Header Parsing Differences (e.g., Transfer-Encoding, Content-Length) [HIGH-RISK PATH] │ │ │ │ │ └── Craft requests with ambiguous header combinations to bypass security checks or route requests unexpectedly. [HIGH-RISK PATH] │ │ ├─── Header Injection Attacks [CRITICAL NODE, HIGH-RISK PATH] │ │ │ ├───[AND] Insufficient Header Sanitization [HIGH-RISK PATH] │ │ │ │ └── Inject malicious headers (e.g., \r\n sequences) to manipulate application behavior or backend systems. [HIGH-RISK PATH] │ │ ├─── Body Parsing Vulnerabilities [CRITICAL NODE, HIGH-RISK PATH] │ │ │ ├───[AND] Denial of Service via Large Bodies [HIGH-RISK PATH] │ │ │ │ └── Send extremely large request bodies to exhaust server resources (memory, CPU). [HIGH-RISK PATH] │ │ ├─── WebSocket Vulnerabilities (if enabled and used) [HIGH-RISK PATH] │ │ │ ├───[AND] WebSocket Protocol Flaws [HIGH-RISK PATH] │ │ │ │ └── Resource Exhaustion via WebSocket Connections [HIGH-RISK PATH] │ │ │ │ └── Open numerous WebSocket connections to exhaust server resources. [HIGH-RISK PATH] │ ├───[OR] Denial of Service (DoS) Attacks [CRITICAL NODE, HIGH-RISK PATH] │ │ ├─── Resource Exhaustion Attacks [CRITICAL NODE, HIGH-RISK PATH] │ │ │ ├───[AND] Connection Exhaustion [HIGH-RISK PATH] │ │ │ │ └── Open a large number of connections to exhaust connection limits and prevent legitimate users from connecting. [HIGH-RISK PATH] │ │ │ ├───[AND] CPU Exhaustion [HIGH-RISK PATH] │ │ │ │ ├─── Slowloris Attacks [HIGH-RISK PATH] │ │ │ │ │ └── Send slow, incomplete requests to keep connections open and exhaust server resources. [HIGH-RISK PATH] │ │ │ │ ├─── Request Flooding [HIGH-RISK PATH] │ │ │ │ │ └── Send a high volume of requests to overwhelm the server's processing capacity. [HIGH-RISK PATH]

Attack Tree Path: Critical Node: Attack Goal: Compromise fasthttp Application

This is the ultimate objective of the attacker. Success means gaining unauthorized control or causing significant disruption to the application using fasthttp.

Attack Tree Path: Critical Node: Exploit fasthttp Vulnerabilities

This represents the primary attack strategy. The attacker aims to find and leverage weaknesses or vulnerabilities specifically within the fasthttp library itself, rather than generic web application flaws.

Attack Tree Path: Critical Node & High-Risk Path: Request Handling Vulnerabilities

This category encompasses vulnerabilities arising from how fasthttp processes incoming HTTP requests. It's high-risk because request handling is fundamental to any web server, and flaws here can have wide-ranging consequences.

Attack Tree Path: High-Risk Path: HTTP Request Smuggling

Attack Vector: Exploits discrepancies in how fasthttp and other HTTP components (like proxies or backend servers) parse HTTP requests, particularly headers like Transfer-Encoding and Content-Length. * How it works: Attackers craft ambiguous requests that are interpreted differently by fasthttp and another component in the request chain. This allows them to "smuggle" a second request within the first one, leading to request misrouting, bypassing security controls, or cache poisoning. * Potential Impact: Bypassing authentication, unauthorized access to resources, cache poisoning, XSS via cache poisoning, routing requests to unintended backends. * Mitigation: Strict adherence to HTTP standards in fasthttp's parsing, consistent header handling, input validation, regular security audits focusing on request smuggling.

Attack Tree Path: High-Risk Path: Parsing Inconsistencies

Attack Vector: Focuses on specific parsing differences within request smuggling, particularly related to header parsing and URL parsing. * How it works: Attackers leverage subtle variations in how fasthttp interprets headers (like Transfer-Encoding, Content-Length combinations) or URLs compared to other systems. * Potential Impact: Same as HTTP Request Smuggling. * Mitigation: Rigorous testing of header and URL parsing in fasthttp, ensuring consistency with HTTP standards and common HTTP infrastructure.

Attack Tree Path: High-Risk Path: Header Parsing Differences (e.g., Transfer-Encoding, Content-Length)

Attack Vector: Specifically targets ambiguities and edge cases in parsing Transfer-Encoding and Content-Length headers, which are common vectors for request smuggling. * How it works: Crafting requests with combinations of these headers that lead to different interpretations by different HTTP parsers. * Potential Impact: Same as HTTP Request Smuggling. * Mitigation: Strict and unambiguous parsing logic for Transfer-Encoding and Content-Length, prioritizing standard-compliant behavior.

Attack Tree Path: High-Risk Path: Craft requests with ambiguous header combinations to bypass security checks or route requests unexpectedly.

Attack Vector: The actionable step in exploiting header parsing differences for request smuggling. * How it works: Actively crafting and sending requests designed to trigger parsing inconsistencies and achieve smuggling. * Potential Impact: Same as HTTP Request Smuggling. * Mitigation: All mitigations for Request Smuggling and Parsing Inconsistencies apply.

Attack Tree Path: High-Risk Path: Header Injection Attacks

Attack Vector: Exploits insufficient sanitization of HTTP headers by the application or fasthttp itself, allowing attackers to inject malicious headers. * How it works: Attackers include control characters like \r\n within header values. If not properly sanitized, these can be interpreted as header separators, allowing injection of new headers. * Potential Impact: HTTP Response Splitting (if reflected in responses), session fixation, cache poisoning, manipulation of backend systems if headers are forwarded. * Mitigation: Strict header sanitization, removing or encoding control characters, avoiding reflection of user-supplied headers, principle of least privilege for header processing.

Attack Tree Path: High-Risk Path: Insufficient Header Sanitization

Attack Vector: The root cause of Header Injection attacks. * How it works: Lack of proper input validation and sanitization on HTTP headers processed by fasthttp or the application. * Potential Impact: Header Injection Attacks. * Mitigation: Implement robust header sanitization routines in the application and ensure fasthttp itself handles headers safely.

Attack Tree Path: High-Risk Path: Inject malicious headers (e.g., \r\n sequences) to manipulate application behavior or backend systems.

Attack Vector: The actionable step in performing Header Injection attacks. * How it works: Actively crafting and sending requests with malicious headers containing control characters. * Potential Impact: Header Injection Attacks. * Mitigation: All mitigations for Header Injection and Insufficient Header Sanitization apply.

Attack Tree Path: High-Risk Path: Body Parsing Vulnerabilities (specifically Denial of Service via Large Bodies)

Attack Vector: Focuses on DoS attacks by sending excessively large request bodies. * How it works: Attackers send requests with extremely large Content-Length values or very large chunked bodies. If fasthttp or the application doesn't have proper limits, this can exhaust server resources (memory, CPU) leading to DoS. * Potential Impact: Denial of Service. * Mitigation: Implement request body size limits in fasthttp configuration or application logic, resource monitoring, rate limiting.

Attack Tree Path: High-Risk Path: Denial of Service via Large Bodies

Attack Vector: Specific DoS attack using large bodies. * How it works: Sending requests with oversized bodies to overwhelm server resources. * Potential Impact: Denial of Service. * Mitigation: Request body size limits, resource monitoring, DoS protection mechanisms.

Attack Tree Path: High-Risk Path: Send extremely large request bodies to exhaust server resources (memory, CPU).

Attack Vector: The actionable step in DoS via large bodies. * How it works: Actively sending requests with oversized bodies. * Potential Impact: Denial of Service. * Mitigation: All mitigations for DoS via Large Bodies apply.

Attack Tree Path: High-Risk Path: WebSocket Vulnerabilities (specifically Resource Exhaustion via WebSocket Connections)

Attack Vector: DoS attack by exhausting server resources through excessive WebSocket connections. * How it works: Attackers open a large number of WebSocket connections to the fasthttp server. If connection limits are not properly configured or resource management is inefficient, this can exhaust server resources (connection table, memory, CPU) leading to DoS. * Potential Impact: Denial of Service. * Mitigation: Configure connection limits for WebSocket connections, resource monitoring, rate limiting for connection establishment, proper WebSocket connection lifecycle management.

Attack Tree Path: High-Risk Path: WebSocket Protocol Flaws (specifically Resource Exhaustion via WebSocket Connections)

Attack Vector: Focuses on protocol flaws leading to resource exhaustion via WebSockets. * How it works: Exploiting weaknesses in WebSocket handling to cause resource depletion, specifically through connection exhaustion. * Potential Impact: Denial of Service. * Mitigation: Connection limits, resource monitoring, secure WebSocket implementation in fasthttp and application.

Attack Tree Path: High-Risk Path: Resource Exhaustion via WebSocket Connections

Attack Vector: Specific DoS attack using WebSocket connection exhaustion. * How it works: Opening numerous WebSocket connections to overwhelm server resources. * Potential Impact: Denial of Service. * Mitigation: Connection limits, resource monitoring, DoS protection mechanisms.

Attack Tree Path: High-Risk Path: Open numerous WebSocket connections to exhaust server resources.

Attack Vector: The actionable step in DoS via WebSocket connection exhaustion. * How it works: Actively establishing a large number of WebSocket connections. * Potential Impact: Denial of Service. * Mitigation: All mitigations for DoS via WebSocket connection exhaustion apply.

Attack Tree Path: Critical Node & High-Risk Path: Denial of Service (DoS) Attacks

This is a major category of threats against any web server, including those using fasthttp. DoS attacks aim to make the application unavailable to legitimate users.

Attack Tree Path: Critical Node & High-Risk Path: Resource Exhaustion Attacks

This is a common method for achieving DoS. Attackers aim to exhaust critical server resources like connections, CPU, or memory.

Attack Tree Path: High-Risk Path: Connection Exhaustion

Attack Vector: DoS attack by exhausting the server's connection limits. * How it works: Attackers open a large number of connections to the fasthttp server, exceeding its configured connection limits. This prevents legitimate users from establishing new connections, leading to DoS. * Potential Impact: Denial of Service. * Mitigation: Configure connection limits, implement connection rate limiting, use connection pooling, resource monitoring.

Attack Tree Path: High-Risk Path: Open a large number of connections to exhaust connection limits and prevent legitimate users from connecting.

Attack Vector: The actionable step in Connection Exhaustion DoS. * How it works: Actively opening a large volume of connections. * Potential Impact: Denial of Service. * Mitigation: All mitigations for Connection Exhaustion DoS apply.

Attack Tree Path: High-Risk Path: CPU Exhaustion

Attack Vector: DoS attack by overloading the server's CPU.

Attack Tree Path: High-Risk Path: Slowloris Attacks

Attack Vector: A type of CPU exhaustion attack that slowly sends incomplete HTTP requests to keep connections open for a long time, eventually exhausting connection resources and CPU. * How it works: Attackers send slow, incomplete requests (e.g., sending headers but not the body, or sending headers very slowly). This keeps connections in a pending state, consuming server resources and eventually leading to connection and CPU exhaustion. * Potential Impact: Denial of Service. * Mitigation: Implement timeouts for connection inactivity and request completion, rate limiting, use a reverse proxy or WAF with Slowloris protection.

Attack Tree Path: High-Risk Path: Send slow, incomplete requests to keep connections open and exhaust server resources.

Attack Vector: The actionable step in Slowloris attacks. * How it works: Actively sending slow, incomplete requests. * Potential Impact: Denial of Service. * Mitigation: All mitigations for Slowloris attacks apply.

Attack Tree Path: High-Risk Path: Request Flooding

Attack Vector: A basic DoS attack by overwhelming the server with a high volume of legitimate-looking requests. * How it works: Attackers send a massive number of requests to the fasthttp server in a short period. If the server's processing capacity is exceeded, it becomes overloaded and unable to respond to legitimate requests, leading to DoS. * Potential Impact: Denial of Service. * Mitigation: Rate limiting, traffic filtering, use a CDN or DDoS protection service, resource monitoring.

Attack Tree Path: High-Risk Path: Send a high volume of requests to overwhelm the server's processing capacity.

Attack Vector: The actionable step in Request Flooding DoS. * How it works: Actively sending a large volume of requests. * Potential Impact: Denial of Service. * Mitigation: All mitigations for Request Flooding DoS apply.