mPDF through 7.1.6, if deployed as a web application that accepts arbitrary HTML, allows SSRF, as demonstrated by a '<img src="http://192.168' substring that triggers a call to getImage in Image/ImageProcessor.php. NOTE: the software maintainer disputes this, stating "If you allow users to pass HTML without sanitising it, you're asking for trouble.

mPDF version 7.1.7 and earlier contains a CWE-502: Deserialization of Untrusted Data vulnerability in getImage() method of Image/ImageProcessor class that can result in Arbitry code execution, file write, etc.. This attack appears to be exploitable via attacker must host crafted image on victim server and trigger generation of pdf file with content <img src="phar://path/to/crafted/image">. This vulnerability appears to have been fixed in 7.1.8.

mPDF 7.0 contains a local file inclusion vulnerability that allows attackers to read arbitrary system files by manipulating annotation file parameters. Attackers can generate URL-encoded or base64 payloads to include local files through crafted annotation content with file path specifications.