> This material is prosecuted under a "strict liability." It doesn't matter how you got it, you're liable.
You're overselling it.
First, there is a statutory affirmative defense: if I obtain CSAM and "promptly and in good faith" delete it or report what happened to law enforcement, liability does not attach.
Additionally, federal laws are clear that you have to knowingly receive CSAM. That's not just a legal flourish or a word – knowledge is an element that a jury or judge will rule on. If I ask you to send me an illegal video and you do, we've both knowingly violated federal law. If you send me to a webpage that purports to offer me a job, but actually has images hidden with CSS to poison my cache, I've not knowingly received anything.
It's not a defense at all. This material is prosecuted under a "strict liability." It doesn't matter how you got it, you're liable.