efilogin-helper Energy Impact CPU High Sierra

efilogin-helper process randomly starts, with > 100 percent energy impact, causing my Macbook to heat up, fans to spin at maximum RPM and remaining battery life to dwindle by around one percent a minute. Process restarts if killed. I have never enabled FileVault. I see reports on this going back to 2015.

Only solution I've found has been to replace my high res desktop background image (preferences -> desktop and screensaver) with a solid color. Is there a solution that allows me to still use a background image for my desktop?