Lab: Reflected XSS into attribute with angle brackets HTML-encoded
Summary: PortSwigger's lab presents a reflected cross-site scripting vulnerability in search blog functionality where angle brackets are HTML-encoded. Solving it requires injecting an attribute that escapes a quoted attribute and calls the alert function, and the lab notes that a payload triggering alert() for the tester may not execute in the victim's browser, so different attributes may need to be tried.
What you should know: The lab's own caveat is the stake: a payload that fires alert() in your browser is not proof it will execute on a victim, so a finding validated only against yourself can leave the reflected XSS live for real users.
Read the original at PortSwigger Research ↗
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