Kimai has an XXE Leading to Local File Read
Summary
Kimai uses PHPSpreadsheet for importing and exporting invoices. Recently, a CVE was identified in PHPSpreadsheet, which could lead to an XXE vulnerability.
Details
Exploitation requires an Administrator account, allowing the upload of an XLSX template containing the payload. The vulnerability is triggered by the following code snippet:
// https://github.com/kimai/kimai/blob/b1903ba18359be16dd32ea9c40377c486498f082/src/Invoice/Renderer/AbstractSpreadsheetRenderer.php#L41
public function render(InvoiceDocument $document, InvoiceModel $model): Response
{
$spreadsheet = IOFactory::load($document->getFilename());
$worksheet = $spreadsheet->getActiveSheet();
$entries = $model->getCalculator()->getEntries();
$sheetReplacer = $model->toArray();
$invoiceItemCount = \count($entries);
if ($invoiceItemCount > 1) {
$this->addTemplateRows($worksheet, $invoiceItemCount);
}
}The IOFactory::load function utilizes simplexml_load_string, which has previously been demonstrated to be vulnerable to XXE attacks.
While this is not directly an XXE in Kimai, it does however impact the latest stable version.
PoC
By uploading a malicious XLSX template, the payload will be triggered every time an invoice is generated.
<?xml version="1.0" encoding='UTF-7' standalone="yes"?>
+ADw-!DOCTYPE foo [ <!ENTITY % xxe SYSTEM "php://filter/......." > %xxe;]>.....For a better a visibility, I will upload both a:
- Malicious template sample for testing
- An exported invoice, showing the contents of target file during the export.
Impact
Local File Read / RCE in edge cases where phar:// can be utilized with gadget chains .
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Composer package | kimai/kimai | < 2.21.0 | 2.21.0 |
References
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N- Weakness (CWE)
CWE-1395, CWE-611- Platform
- Composer
- Package
kimai/kimai- Disclosed
- 17.09.2024
- Updated
- 11.10.2026 10:22
Sources and licenses
OSV / GitHub Advisory Database - GHSA-534c-hcr7-67jg - CC BY 4.0
Vulnerability history: kimai/kimai
All published vulnerabilities of this package (Composer package), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 33
- First → latest
- 02.2023 07.2026
- Without a fix
- 1
- Exploited in attacks
- 0
Severity breakdown
- Critical 2
- High 4
- Medium 20
- Low 7
Disclosures per year
- 2023: 2
- 2024: 3
- 2025: 1
- 2026: 27
-
Kimai has an XXE Leading to Local File Read this entry
Know which vulnerabilities affect your application
With the DockRay integration and software inventory enabled, DockRay checks reported component versions against known vulnerabilities and notifies you about confirmed matches. Coverage depends on the supported technology and available advisory data.