Dompdf is an HTML to PDF converter. The URI validation on dompdf 2.0.1 can be bypassed on SVG parsing by passing `<image>` tags with uppercase letters. This may lead to arbitrary object unserialize on PHP <8,throughthe`phar`URLwrapper.AnattackercanexploitthevulnerabilitytocallarbitraryURLwitharbitraryprotocols,iftheycanprovideaSVGfiletodompdf.InPHPversionsbefore8.0.0,itleadstoarbitraryunserialize,thatwillleadtotheveryleasttoanarbitraryfiledeletionandevenremotecodeexecution,dependingonclassesthatareavailable.