GHSA-rx7m-68vc-ppxh PhpSpreadsheet vulnerable to SSRF when reading and displaying a processed HTML document in the browser

• Packagist phpoffice/phpspreadsheet: < 1.30.0 → fixed in 1.30.0 • Packagist phpoffice/phpspreadsheet: >= 2.0.0, < 2.1.12 → fixed in 2.1.12 • Packagist phpoffice/phpspreadsheet: >= 2.2.0, < 2.4.0 → fixed in 2.4.0 • Packagist phpoffice/phpspreadsheet: >= 3.0.0, < 3.10.0 → fixed in 3.10.0 • Packagist phpoffice/phpspreadsheet: >= 4.0.0, < 5.0.0 → fixed in 5.0.0

Product: PhpSpreadsheet Version: 3.8.0 CWE-ID: CWE-918: Server-Side Request Forgery (SSRF) CVSS vector v.3.1: 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N) CVSS vector v.4.0: 8.7 (AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N) Description: SSRF occurs when a processed HTML document is read and displayed in the browser Impact: Server-Side Request Forgery Vulnerable component: the `PhpOffice\PhpSpreadsheet\Worksheet\Drawing` class, `setPath` method Exploitation conditions: getting a string from the user that is passed to the HTML reader Mitigation: improved processing of the `$path` variable of the `setPath` method of the `PhpOffice\PhpSpreadsheet\Worksheet\Drawing` class is needed Researcher: Aleksey Solovev (Positive Technologies) Research The researcher discovered zero-day vulnerability Server-Side Request Forgery (SSRF) (in the `setPath` method of the `PhpOffice\PhpSpreadsheet\Worksheet\Drawing` class) in Phpspreadsheet. The latest version (3.8.0) of the `phpoffice/phpspreadsheet` library was installed. Below are the details of the installation: *Listing 1. Installing the phpoffice/phpspreadsheet library* ``` $ composer require phpoffice/phpspreadsheet --prefer-source ``` The code that processes the HTML string with further rendering and displaying the result in the browser. *Listing 2. Executable file index.php using the PhpSpreadsheet library* ``` load($inputFileName); $writer = new \PhpOffice\PhpSpreadsheet\Writer\Html($spreadsheet); print($writer->generateHTMLAll()); ``` Also, the `./doc/file.html` has the following content: the `img` tag with the `src` attribute, which contains the value `http:// 127.0.0.1:1337` *Listing 3. The ./doc/file.html file* ``` ``` The vulnerability lies in the `setPath` method of the `PhpOffice\PhpSpreadsheet\Worksheet\Drawing` class. Figure 1. The `PhpOffice\PhpSpreadsheet\Worksheet\Drawing` class, `setPath` method. Figure 2 below demonstrates the SSRF vulnerability exploitation. Figure 2. Demonstration of the SSRF vulnerability exploitation Also, there is code on line 154 that could potentially be used by an attacker to perform unsafe deserialization via the `phar` archive and the `file_exists` method. Figure 3. Opportunity to perform phar deserialization _____________________________________________ Please, assign all credits to: Aleksey Solovev (Positive Technologies) Credit Aleksey Solovev (Positive Technologies)