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GHSA-wv23-996v-q229

MEDIUM

PhpSpreadsheet has a Cross-Site Scripting (XSS) vulnerability in custom properties

Also known asCVE-2024-56410
Published
Jan 3, 2025
Updated
Mar 6, 2025
Affected
5 pkgs
Patched
4 / 5
Exploits
None indexed

EPSS Exploitation Probability

via FIRST.org ↗
0.3%probability of exploitation in next 30 days
Lower Risk23th percentile-0.59%
0.00%0.47%0.94%1.41%0.2%0.3%Dec 25Apr 26Jun 26

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Blast Radius

5 pkgs affected
🐘phpoffice/phpspreadsheet🐘phpoffice/phpspreadsheet🐘phpoffice/phpspreadsheet🐘phpoffice/phpspreadsheet🐘phpoffice/phpexcel

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.

Description

Cross-Site Scripting (XSS) vulnerability in custom properties

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: 5.4 (AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N) CVSS vector v.4.0: 4.8 (AV:N/AC:L/AT:N/PR:L/UI:A/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N) Description: the HTML page is generated without clearing custom properties Impact: executing arbitrary JavaScript code in the browser Vulnerable component: class PhpOffice\PhpSpreadsheet\Writer\Html, method generateMeta Exploitation conditions: a user viewing a specially generated Excel file Mitigation: additional sanitization of special characters in a string Researcher: Aleksey Solovev (Positive Technologies)

Research

The researcher discovered zero-day vulnerability Cross-Site Scripting (XSS) vulnerability in custom properties in Phpspreadsheet. The following code is written on the server, which translates the XLSX file into a HTML representation and displays it in the response.

Listing 9. Source code on the server

<?php

require __DIR__ . '/vendor/autoload.php';

$inputFileName = './doc/Book1.xlsx';
$spreadsheet = \PhpOffice\PhpSpreadsheet\IOFactory::load($inputFileName);
$writer = new \PhpOffice\PhpSpreadsheet\Writer\Html($spreadsheet);
print($writer->generateHTMLAll());

An attacker can embed a payload in a file property that will result in the execution of arbitrary JavaScript code. The Excel file is unpacked and a custom property in the file is inserted into the docProps/custom.xml file.

fig17

Figure 17. Embedding the payload

After making the changes, a new archive with the xlsx extension was created. At the moment of converting the xlsx file into an HTML representation, a property is obtained that participates in the formation of a string without sanitization.

fig18

Figure 18. Getting a custom property

When calling the static generateMeta method, you can see that the key of the custom property is displayed without sanitization.

fig19

Figure 19. Getting a custom property

As a result, when viewing the excel file as the HTML representation, arbitrary JavaScript code will be executed.

<img width="356" alt="fig20" src="https://github.com/user-attachments/assets/a6ed21e3-685c-415c-b2dc-453bc0652bef" />

Figure 20. Executing arbitrary JavaScript code

Credit

This vulnerability was discovered by Aleksey Solovev (Positive Technologies)

Affected Packages

5 total 4 fixed
EcosystemPackageVulnerable rangeFix
🐘Packagistphpoffice/phpspreadsheet3.0.0&&< 3.7.03.7.0
🐘Packagistphpoffice/phpspreadsheetall versions1.29.7
🐘Packagistphpoffice/phpspreadsheet2.0.0&&< 2.1.62.1.6
🐘Packagistphpoffice/phpspreadsheet2.2.0&&< 2.3.52.3.5
🐘Packagistphpoffice/phpexcelall versionsNo fix

Detection & mitigation playbook

Open-source dependency
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for phpoffice/phpspreadsheet. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

  2. Fix

    Update phpoffice/phpspreadsheet to 3.7.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-wv23-996v-q229 is resolved across your whole dependency graph.

  3. Workarounds

    If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

  4. How O3 protects you

    O3 pinpoints whether GHSA-wv23-996v-q229 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-wv23-996v-q229. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

# Cross-Site Scripting (XSS) vulnerability in custom properties **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**: 5.4 (AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N) **CVSS vector v.4.0**: 4.8 (AV:N/AC:L/AT:N/PR:L/UI:A/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N) **Description**: the HTML page is generated without clearing custom properties **Impact**: executing arbitrary JavaScript code in the browser **Vulnerable component**: class `PhpOffice\PhpSpreadsheet\Writer\Html`, method `gene
O3 Security · Impact-Aware SCA

Is GHSA-wv23-996v-q229 in your dependencies?

O3 detects GHSA-wv23-996v-q229 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.