linktolocalpath in ebooks/conversion/plugins/htmlinput.py in calibre before 6.19.0 can, by default, add resources outside of the document root.
{
"cpe": "cpe:2.3:a:calibre-ebook:calibre:*:*:*:*:*:*:*:*",
"source": "CPE_FIELD",
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "6.19.0"
}
]
}