Before turning to unconventional methods of usage, I will describe how “keep-alive” is working. The process is utterly simple – in a connection, multiple requests are sent instead of just one, and multiple responses come from the server. The benefits are obvious: there is less time spent on establishing connection, less load on CPU and memory. The number of requests in a single connection is usually limited by settings of the server (in most cases, there are at least several dozen). The procedure for establishing a connection is universal.
Philip Kucheryavy, Software Engineer in the Operations Team
- He is 24 and has a beard
- In love with Linux and Python
- Has no diploma of higher education
*nix systems are by default provided with remote management tools, while the method of storing and format of configuration files allows you to rapidly distribute the updated version of settings by simply copying them to the node. This scheme will be good enough for up to a certain number of systems. However, when there are several dozens of servers, they cannot be handled without a special tool. This is when it becomes interesting to have a look at configuration management systems that allow a programmable rather than manual configuration of servers. As a result, the systems can be configured quickly and with fewer errors while the administrator will get the comprehensive report. Also, a CM system knows how to keep track of all changes in the server while supporting the desired configuration.
Often, the manufacturers of routers do not particularly care about the quality of their code. As a result, the vulnerabilities are not uncommon. Today, the routers are a priority target of network attacks that allows to steal money and data while bypassing local protection systems. How can you personally check the quality of firmware and adequacy of settings? You can do this by using free utilities, online test services and this article.
Task: Set up Cisco as server
Today we are going to cover the topic of Cisco-device (routers, switches) hacking, so to say, carrying on with the once started. Here I would like to amend the information which was presented in the previous issue. First, these devices have not two but three variants of user isolation: by password only, by login and password, or in “AAA” model (also by login and password). There seems to be no practical difference for a pen tester, but we’d still better rely on valid information.
Outer Perimeter: The Listener is under Attack
Those who ever came across this database know that Oracle DB interacts with its external environment by using a listener, which is a kind of balancer. The listener listens to port 1521 and resolves incoming connections depending on the requested database. One listener allows you to serve different databases. Also, in some cases, it allows to launch DoS and RCE attacks against the server. The audit of an Oracle database usually begins with attacks against the listener service. A priority task that you need to resolve in order to connect to the listener is to get SID, a kind of unique database identifier. Without it, the listener will not communicate with you. Sh2kerr once wrote an excellent research paper on this subject (Different ways to guess Oracle database SID).
We will start with a definition. MySQL is a relational database management system with different data storage engines, such as MyISAM, InnoDB, Archive and others. Like most open source projects, it has its own branches, for example, MariaDB. Before going into details, I would like to mention that most of discussed vectors/techniques/bugs apply to various engines and branches, though not always.