Explore the world of headless browsers and their impact on web application security in this 44-minute conference talk from OWASP AppSecUSA 2014. Dive into the offensive use of tools like PhantomJS for finding vulnerabilities and automating attacks, as well as defensive strategies to counteract malicious activities. Learn techniques for detecting and exposing impersonation attempts, collecting threat forensics, and attaining attacker attribution data. Discover vulnerabilities in headless browsers themselves and gain insights on using these tools safely. Through demonstrations and examples, understand how to leverage headless browsers for security testing while protecting against potential exploits.