Language: PHP
Label: vulnerable
CWE: CWE-79 \u2014 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

Code:
    protected function getDocumentPreviewPdf(Asset\Document $asset)
    {
        $stream = null;

        if ($asset->getMimeType() == 'application/pdf') {
            $stream = $asset->getStream();
        }

        if (!$stream && $asset->getPageCount() && \Pimcore\Document::isAvailable() && \Pimcore\Document::isFileTypeSupported($asset->getFilename())) {
            try {
                $document = \Pimcore\Document::getInstance();
                $stream = $document->getPdf($asset);
            } catch (\Exception $e) {
                // nothing to do
            }
        }

        return $stream;
    }