Posts

Symetric Denial of Service Testing - Aka 1 on 1

Intro This post is going to explain how to test a Denial of Service Vulnerability without crashing the actual service. More specifically we will focus on two vulnerabilities a) the slowris vulnerability (also known as Apache Partial HTTP Request Denial of Service Vulnerability) and b) the TLS Renegotiation and Denial of Service Attacks. Apache Partial HTTP Request Denial of Service Vulnerability The target application Apache Server is vulnerable to a denial of service named Slow-DoS attack, due to holding a connection open for partial HTTP requests. Both Apache Versions 1.x and 2.x are vulnerable. Slow HTTP attacks are denial-of-service (DoS) attacks in which the attacker sends HTTP requests in pieces slowly, one at a time to a Web server. If an HTTP request is not complete, or if the transfer rate is very low, the server keeps its resources busy waiting for the rest of the data. When the server’s concurrent connection pool reaches its maximum, this creates a DoS. Slow HTTP attac...

Apache mod_negotiation or MultiViews filename bruteforcing

Filename   Brute-forcing  through MultiViews Vulnerability This is a small post about a way to easily get backup files on Apache web servers with Multiviews option enabled. There is no much information in Multiviews (an Apache feature) and some Web Application scanners report this as Apache mod_negotiation filename brute-forcing rather than Multiviews option enabled. Apache HTTPD supports content negotiation as described in the HTTP/1.1 specification (see http://www.w3.org/Protocols/rfc2616/rfc2616.html ). It can choose the best representation of a resource based on the browser-supplied preferences for media type, languages, character set and encoding. It also implements a couple of features to give more intelligent handling of requests from browsers that send incomplete negotiation information. What are resources A resource is a conceptual entity identified by a URI (RFC 2396). An HTTP server like Apache HTTP Server provides access to representations of the resource(s...