What might you use this payload for?

Preventing OS command injection is simpler than patching a breach. But many devs still make the same critical mistakes. 5 ways to prevent OS command injection👇 1️⃣ Avoid Calling OS Commands from App Code Never rely on exec(), system(), or similar to handle logic from user input. In nearly all cases, there are safer platform APIs that accomplish the same task. If you can avoid the shell, avoid it. 2️⃣ Use Safer Alternatives (APIs > Shell) For file manipulation, networking, or system info — languages like Python, Java, and Node have built-in libraries. Use those over invoking commands like rm, ping, or ls. 3️⃣ Use Strict Input Validation If you must use OS calls, validate inputs: ✅ Whitelist allowed values ✅ Ensure input is numeric if expected ✅ Allow only alphanumeric characters (no symbols or whitespace) Never rely on blacklisting or pattern matching alone. 4️⃣ Do NOT Escape Shell Metacharacters Trying to escape metacharacters like &, ;, or | is error-prone and dangerous. Attackers know how to bypass these filters. Escaping isn’t prevention. It’s a false sense of security. 5️⃣ Design for Defense, Not Detection The goal is to eliminate the attack surface, not just catch bad input. Avoiding dangerous code paths is always more reliable than filtering them. Secure-by-design means zero shell calls = zero shell injection risk. Avoid the shell. Validate everything. Never trust user input. Learn more: portswigger.net/web-security…

5 ways to bypass path traversal filters👇

What is OS command injection? In this video, we explore how OS command injection vulnerabilities are discovered, exploited, and mitigated. You’ll learn: 🔸 What OS command injection is and why it’s dangerous 🔸 Practical techniques attackers use for both visible and blind exploitation 🔸 Real payload examples including echo, ping, nslookup 🔸 How to detect and test using chaining, timing, or DNS 🔸 Secure coding practices and input validation for prevention Watch now: youtube.com/watch?v=8PDDjCW5…

Put your recon skills to the test with a mystery lab! 🔮 We'll hide the lab title and description o you can put your recon skills to the test! You won't even know what vulnerability you're looking for! Get your mystery lab now 👇 portswigger.net/web-security…

APPRENTICE Lab: Stored XSS into anchor href attribute with double quotes HTML-encoded In this lab, you'll learn how to: 1. Discover Stored XSS Vulnerabilities Identify how user input (like a commenter's website) can be stored and rendered insecurely. 2. Analyze Reflected HTML Contexts Use Burp Suite to find exactly where and how your input appears in the DOM — specifically inside HTML attributes. 3. Craft XSS Payloads for Anchor Hrefs Inject a javascript: URI to trigger JavaScript execution when the anchor () is clicked. 4. Bypass HTML Encoding Safely Understand how even double-quote-encoded attributes can still be exploited with correctly placed payloads. 5. Confirm XSS Execution Validate your exploit by interacting with the application as a real user (e.g. clicking your own comment name). Try this lab now: portswigger.net/web-security…

Path traversal bugs let attackers access sensitive files on your server. Most apps don’t need to allow this (yet many do). 5 steps to preventing traversal attacks👇 1️⃣ Avoid filesystem access from user input The safest solution is simply not using user-supplied paths in file operations. Rewriting functionality to avoid it altogether is the most secure approach. 2️⃣ Use a whitelist of permitted values If input is needed, validate it strictly. Best option: compare against a fixed set of allowed filenames or tokens — not patterns. 3️⃣ Use character-level validation When a full whitelist isn’t possible, restrict input to alphanumerics only. Disallow . .. / \ and other special characters attackers rely on. 4️⃣ Canonicalize the full file path Use your platform’s filesystem API (e.g. getCanonicalPath() in Java) to resolve the absolute path. This normalizes input and defeats encoding tricks. 5️⃣ Check path is within base directory After canonicalizing, confirm the resolved path starts with your base directory: File file = new File(BASE_DIRECTORY, userInput); if (file.getCanonicalPath().startsWith(BASE_DIRECTORY)) { // process file } Path traversal is preventable with proper input handling and path validation. Learn more about Path Traversal here: portswigger.net/web-security…

Need help with SQL injection? Here's our cheatsheet: portswigger.net/web-security…