Vulnerability field guide

Cross-Site Scripting

Cross-site scripting lets attacker-controlled input run as JavaScript in a victim's browser. Here is what XSS is, how its three variants differ, and the layered defence that shuts all of them down.

6 articles24 min totalOverview to advanced techniques
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Step 01 · Start with the overview
Cross-Site Scripting3 min read

Cross-Site Scripting, Explained: Reflected, Stored and DOM-Based XSS

Cross-site scripting lets attacker-controlled input run as JavaScript in a victim's browser. Here is what XSS is, how its three variants differ, and the layered defence that shuts all of them down.

Read the overview
Continue the field guide

Cross-Site Scripting techniques

5 focused deep-dives
  1. 02BlindBlind XSS: When Your Payload Fires in an Admin Panel You Never See5 min
  2. 03DOM-BasedDOM-Based XSS: When the Vulnerability Never Touches the Server4 min
  3. 04Mutation (mXSS)Mutation XSS (mXSS): How the Browser's Parser Rewrites Your Sanitized HTML6 min
  4. 05ReflectedReflected XSS: How a URL Can Run Code in Someone Else's Browser3 min
  5. 06StoredStored XSS: One Injection, Every Visitor3 min