High

PhpSpreadsheet allows unauthorized Reflected XSS in the constructor of the Downloader class

  • Disclosed: 03.01.2025
  • Updated: 11.10.2026 10:22

Unauthorized Reflected XSS in the constructor of the Downloader class

Product: Phpspreadsheet Version: version 3.6.0 CWE-ID: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') CVSS vector v.3.1: 8.2 (AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A: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) Description: using the /vendor/phpoffice/phpspreadsheet/samples/download.php script, an attacker can perform a XSS-type attack Impact: execution of arbitrary JavaScript code in the browser Vulnerable component: the constructor of the Downloader class Exploitation conditions: an unauthorized user Mitigation: sanitization of the name and type variables Researcher: Aleksey Solovev (Positive Technologies)

Research

The researcher discovered zero-day vulnerability Unauthorized Reflected Cross-Site Scripting (XSS) (in the constructor of the Downloader class) in Phpspreadsheet.

The latest version (3.6.0) of the phpoffice/phpspreadsheet library was installed. The installation was carried out with the inclusion of examples.

Listing 1. Installing the phpoffice/phpspreadsheet library

bash
$ composer require phpoffice/phpspreadsheet --prefer-source

The ./vendor/phpoffice/phpspreadsheet/samples/download.php file processes the GET parameters name and type.

fig1

Figure 1. The ./vendor/phpoffice/phpspreadsheet/samples/download.php file accepts GET parameters.

Consider the constructor of the Downloader class, where GET parameters are passed. Error is displayed without sanitization using GET parameters transmitted from the user.

fig2

Figure 2. Error is displayed without sanitization

When clicking on the following link, arbitrary JavaScript code will be executed.

Listing 2.

https://192.***.***.***/vendor/phpoffice/phpspreadsheet/samples/download.php?name=%3Cimg%20src=1%20onerror=alert()%3E&type=1

Demonstration of the execution of arbitrary JavaScript code.

<img width="537" alt="fig3" src="https://github.com/user-attachments/assets/745d6e21-396f-4357-8ff8-e856adf15fee" />

Figure 3. Executing arbitrary JavaScript code

Credit

This vulnerability was discovered by Aleksey Solovev (Positive Technologies)

Affected software

Click a technology to see all vulnerabilities affecting it.

PlatformPackageVulnerable versionsFixed in
Composer package phpoffice/phpexcel <= 1.8.2 no fix
Composer package phpoffice/phpspreadsheet >= 3.0.0, < 3.7.0, < 1.29.7, >= 2.0.0, < 2.1.6, >= 2.2.0, < 2.3.5 3.7.0, 1.29.7, 2.1.6, 2.3.5

References

CVSS score 7.1/10
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:N
Weakness (CWE)
CWE-79
Platform
Composer
Package
phpoffice/phpexcel, phpoffice/phpspreadsheet
Disclosed
03.01.2025
Updated
11.10.2026 10:22

Sources and licenses

OSV / GitHub Advisory Database - GHSA-jmpx-686v-c3wx - CC BY 4.0

Vulnerability history: phpoffice/phpexcel

All published vulnerabilities of this package (Composer package), newest first. Shows whether this is a one-off slip or a package that needs watching.

All (23) in the archive
Total entries
23
First → latest
11.2019 02.2025
Without a fix
20
Exploited in attacks
0

Severity breakdown

  • High 12
  • Medium 10
  • Low 1

Disclosures per year

  1. 2019: 2
  2. 2020: 0
  3. 2021: 1
  4. 2022: 1
  5. 2023: 0
  6. 2024: 10
  7. 2025: 9
  8. 2026: 0
Severity:
  1. PhpSpreadsheet allows unauthorized Reflected XSS in the constructor of the Downloader class this entry
    High · 7.1 CVE-2024-56365 <= 1.8.2 no fix
  2. High · 7.5 CVE-2024-48917 <= 1.8.2 no fix
  3. High · 7.5 CVE-2024-47873 <= 1.8.2 no fix
  4. High CVE-2015-3542 < 1.8.1 1.8.1
  5. High · 7.5 CVE-2024-45293 <= 1.8.2 no fix
  6. High · 8.8 CVE-2024-45048 <= 1.8.2 no fix
  7. High · 8.8 CVE-2018-19277 < 1.8.2 1.8.2

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