TA0005 · DEFENSE EVASION
HTML Smuggling
Adversaries may smuggle data and files past content filters by hiding malicious payloads inside of seemingly benign HTML files.
Detect it with
Detection of HTML Smuggling is difficult as HTML5 and JavaScript attributes are used by legitimate services and applications.
Why it matters on shift
HTML Smuggling is one of the concrete ways adversaries achieve defense evasion. Recognising it in telemetry lets you name the technique in your ticket and pivot to what came before and after.
What to look for next
After defense evasion, the next tactic is usually Credential Access. Search your telemetry for the transition before closing the ticket.
Kill-chain context