CVE-2026-44298

Users with the role System-Admin (ROLE_SYSTE_ADMIN) and the permission upload_invoice_template can upload PDF invoice templates, which can call pdfContext.setOption('associated_files', ...) inside the sandboxed Twig render.

This is forwarded to mPDF's SetAssociatedFiles(), whose writer calls file_get_contents($entry['path']) during PDF output and embeds the bytes as a FlateDecode stream in the PDF. Any file readable by the PHP worker is returned to the attacker inside the rendered invoice.

Root cause

1. src/Twig/SecurityPolicy/StrictPolicy.php:123-128 explicitly whitelists PdfContext::setOption():

   if ($obj instanceof PdfContext) {
       if ($lcm !== 'setoption') { throw ...; }
       return;
   }
   

2. src/Pdf/MPdfConverter.php keeps associated_files in the pass-through allowlist:

   $allowed = ['mode','format','default_font_size','default_font', ... , 'associated_files','additional_xmp_rdf'];
   

   and then forwards it to mPDF:

   if (array_key_exists('associated_files', $options) && is_array($options['associated_files'])) {
       $associatedFiles = $options['associated_files'];
       unset($options['associated_files']);
   }
   ...
   $mpdf->SetAssociatedFiles($associatedFiles);
   

3. mPDF 8.3.1 MetadataWriter::writeAssociatedFiles() calls file_get_contents, which respects PHP stream wrappers:

   if (isset($file['path'])) {
       $fileContent = @file_get_contents($file['path']);
   }
   ...
   $filestream = gzcompress($fileContent);
   $this->writer->write('<</Type /EmbeddedFile');
   

The sandbox and the option allowlist were both written defensively (short whitelists, not blacklists), but neither side considered that associated_files is a PDF/A file-embedding feature whose path key is a sink.

Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files. Typical impact: unauthorized file read or write outside the intended directory.

CVE-2026-44298 has a CVSS score of 4.1 (Medium). The vector is network-reachable, high privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (2.56); upgrading removes the vulnerable code path.

Kodem intelligence

The implemented fix has two aspects:

1. The PdfContext now works with a strict allow-list, that excludes associated_files
2. The MPdfConverter now removes any path from the $associatedFiles array, which can still be used by plugins:

        if (\count($associatedFiles) > 0) {
            // remove "path" so mPDF will not use file_get_contents() on local files
            // callers must pre-read and pass the bytes via "content"
            $associatedFiles = array_map(static function ($entry): array {
                if (!\is_array($entry)) {
                    return [];
                }

                if (\array_key_exists('path', $entry)) {
                    unset($entry['path']);
                }

                return $entry;
            }, $associatedFiles);
            $mpdf->SetAssociatedFiles($associatedFiles);
        }

1. What is CVE-2026-44298? CVE-2026-44298 is a medium-severity path traversal vulnerability in kimai/kimai (composer), affecting versions >= 2.32.0, <= 2.55. It is fixed in 2.56. Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files.
2. How severe is CVE-2026-44298? CVE-2026-44298 has a CVSS score of 4.1 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of kimai/kimai are affected by CVE-2026-44298? kimai/kimai (composer) versions >= 2.32.0, <= 2.55 is affected.
4. Is there a fix for CVE-2026-44298? Yes. CVE-2026-44298 is fixed in 2.56. Upgrade to this version or later.
5. Is CVE-2026-44298 exploitable, and should I be worried? Whether CVE-2026-44298 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2026-44298 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2026-44298? Upgrade kimai/kimai to 2.56 or later.