Practical tutorials for developers and sysadmins
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Practical Security walkthroughs, troubleshooting notes, and best practices.
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Browse every Knowledge Basement article filed under Security.
Learn how to secure AI agents, tool-calling LLM apps, MCP servers, and RAG workflows against prompt injection, data leakage, tool abuse, and AI supply-chain risks.
The first step in a malicious hacker attack is scanning. This means that an attacker will scan its target for open ports and vulnerabilities. So,…
In Java, a resource leak occurs when a program fails to properly release system resources after they are no longer needed. This can lead to a range…
Making methods final in Java can provide several benefits, including: Preventing method overriding: When a method is marked final , it cannot be…
Serializing and deserializing data in Java can introduce several security risks if not implemented properly. Here are some of the main risks: Remote…
In Java, a PreparedStatement is a feature of the JDBC API that allows you to execute parameterized SQL statements. A PreparedStatement is a…
In Java, access modifiers are keywords that determine the accessibility of classes, methods, and variables in an object-oriented program. There are…
Securing a Linux system can be a complex task, and there are many potential pitfalls and mistakes that can compromise the system's security. Here…
iptables and ipsets are both tools that are commonly used in Linux-based operating systems for managing network traffic. However, they serve…
There are several good security practices to follow when developing Java applications. Here are some of the most important ones: Keep your Java…
In Java, objects can be classified as either mutable or immutable based on whether their state can be changed or not. A mutable object is one whose…
Tengine seems to be a popular web server for Chinese websites. I've come upon it while browsing through Aliexpress and stumbling upon a 404 error:…
I've had the following challenge yesterday. A friend of mine had an old Joomla 2.5 with a bunch of customization - additional components installed,…
AppArmor is the default Mandatory Access Control module on Ubuntu, SuSE and other Linux distributions. Thanks to it, you can limit the filesystem…
A great security feature of Php FastCGI Process Manager (Php-fpm) is its ability to run Php scripts with different users. This in addition to its…
Notice: This article was written when SuPHP was the most popular choice for running multiple PHP sites on the same Apache server. Now, php-fpm with…
The MongoDB database server is well-known for its unmatched capabilities for processing large NoSQL data. Its latest performance improvements are…
Almost every piece of information contains sensitive and private data. Exposing publicly such data could lead to serious financial losses, legal…