{"id":"CVE-2024-56365","aliases":["GHSA-jmpx-686v-c3wx"],"url":"https://o3.security/vulnerability/CVE-2024-56365","summary":"PhpSpreadsheet vulnerable to unauthorized reflected XSS in the constructor of the Downloader class","details":"# Unauthorized Reflected XSS in the constructor of the `Downloader` class\n\n**Product**: Phpspreadsheet\n**Version**: version 3.6.0\n**CWE-ID**: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')\n**CVSS vector v.3.1**: 8.2 (AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:N)\n**CVSS vector v.4.0**: 8.3 (AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:H/VA:N/SC:L/SI:H/SA:L)\n**Description**: using the `/vendor/phpoffice/phpspreadsheet/samples/download.php` script, an attacker can perform a XSS-type attack\n**Impact**: execution of arbitrary JavaScript code in the browser\n**Vulnerable component**: the constructor of the `Downloader` class\n**Exploitation conditions**: an unauthorized user\n**Mitigation**: sanitization of the `name` and `type` variables\n**Researcher**: Aleksey Solovev (Positive Technologies)\n\n# Research\n\nThe researcher discovered zero-day vulnerability Unauthorized Reflected Cross-Site Scripting (XSS) (in the constructor of the `Downloader` class) in Phpspreadsheet.\n\nThe latest version (3.6.0) of the `phpoffice/phpspreadsheet` library was installed. The installation was carried out with the inclusion of examples.\n\n*Listing 1. Installing the `phpoffice/phpspreadsheet` library*\n```\n$ composer require phpoffice/phpspreadsheet --prefer-source\n```\n\nThe `./vendor/phpoffice/phpspreadsheet/samples/download.php` file processes the GET parameters `name` and `type`.\n\n![fig1](https://github.com/user-attachments/assets/78d5b3c7-e2ab-4487-98e2-a975f74a71c0)\n\n*Figure 1. The `./vendor/phpoffice/phpspreadsheet/samples/download.php` file accepts GET parameters.*\n\nConsider the constructor of the `Downloader` class, where GET parameters are passed. Error is displayed without sanitization using GET parameters transmitted from the user.\n\n![fig2](https://github.com/user-attachments/assets/00baf1f8-298c-4654-a3e4-b99cf8053eac)\n\n*Figure 2. Error is displayed without sanitization*\n\nWhen clicking on the following link, arbitrary JavaScript code will be executed.\n\n*Listing 2.*\n```\nhttps://192.***.***.***/vendor/phpoffice/phpspreadsheet/samples/download.php?name=%3Cimg%20src=1%20onerror=alert()%3E&type=1\n```\n\nDemonstration of the execution of arbitrary JavaScript code.\n\n<img width=\"537\" alt=\"fig3\" src=\"https://github.com/user-attachments/assets/745d6e21-396f-4357-8ff8-e856adf15fee\" />\n\n*Figure 3. Executing arbitrary JavaScript code*\n\n\n# Credit\nThis vulnerability was discovered by **Aleksey Solovev (Positive Technologies)**","published":"2025-01-03T16:56:35.040Z","modified":"2026-08-12T03:51:21.123841362Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Packagist","name":"phpoffice/phpspreadsheet","fixedVersion":"3.7.0"},{"ecosystem":"Packagist","name":"phpoffice/phpspreadsheet","fixedVersion":"1.29.7"},{"ecosystem":"Packagist","name":"phpoffice/phpspreadsheet","fixedVersion":"2.1.6"},{"ecosystem":"Packagist","name":"phpoffice/phpspreadsheet","fixedVersion":"2.3.5"},{"ecosystem":"Packagist","name":"phpoffice/phpexcel","fixedVersion":null}],"fix":{"url":"https://github.com/PHPOffice/PhpSpreadsheet/commit/700a80346be269af668914172bc6f4521982d0b4#diff-fbb0f53a5c68eeeffaa9ab35552c0b01740396f1a4045af5d2935ec2a62a7816","label":"PHPOffice/PhpSpreadsheet@700a803"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/56xxx/CVE-2024-56365.json"},{"type":"ADVISORY","url":"https://github.com/PHPOffice/PhpSpreadsheet/security/advisories/GHSA-jmpx-686v-c3wx"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-56365"},{"type":"FIX","url":"https://github.com/PHPOffice/PhpSpreadsheet/commit/700a80346be269af668914172bc6f4521982d0b4#diff-fbb0f53a5c68eeeffaa9ab35552c0b01740396f1a4045af5d2935ec2a62a7816"},{"type":"PACKAGE","url":"https://github.com/PHPOffice/PhpSpreadsheet"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:21.123841362Z"}}