Cross-Site Scripting XSS

Introduction to XSS Cross-Site Scripting (XSS) is a client-side vulnerability that appears when user input is rendered as executable JavaScript in the browser. The server is not directly compromised, but the user who loads the page can be targeted for phishing, data theft, or session hijacking. The test goal is to confirm execution, identify how the input is handled, and document a realistic impact. XSS only runs in the browser, so the attack depends on how the page renders or stores input. This is why the same payload can succeed or fail depending on the HTML context. When testing, focus on where the input appears and whether it persists after refresh. Those details determine which attack path is possible. ...

January 5, 2026 · 8 min

Command Injection

Introduction Command Injection is one of the most critical web vulnerabilities because it lets an attacker execute OS commands on the backend host. The impact can be full system compromise and lateral movement if the server has network access. The vulnerability appears when user input is passed into a system command without strict validation and sanitization. This issue is not limited to web apps, but web apps are the most common surface because they regularly call system utilities. If a parameter such as an IP address is used inside a command, a small injection operator can turn it into a full shell. Because the execution happens server-side, any output you can observe is valuable evidence. ...

January 6, 2026 · 8 min