Ecosyste.ms: Advisories

Security Advisories: GSA_kwCzR0hTQS13Z21mLXE5dnItdnd3Ns4AA_Bz

PhpSpreadsheet HTML writer is vulnerable to Cross-Site Scripting via style information

Summary

\PhpOffice\PhpSpreadsheet\Writer\Html doesn't sanitize spreadsheet styling information such as font names, allowing an attacker to inject arbitrary JavaScript on the page.

PoC

Example target script:

<?php

require 'vendor/autoload.php';

$reader = \PhpOffice\PhpSpreadsheet\IOFactory::createReader("Xlsx");
$spreadsheet = $reader->load(__DIR__ . '/book.xlsx');

$writer = new \PhpOffice\PhpSpreadsheet\Writer\Html($spreadsheet);
print($writer->generateHTMLAll());

Save this file in the same directory:
book.xlsx

Open index.php in a web browser. An alert should be displayed.

Impact

Full takeover of the session of users viewing spreadsheet files as HTML.

Permalink: https://github.com/advisories/GHSA-wgmf-q9vr-vww6
JSON: https://advisories.ecosyste.ms/api/v1/advisories/GSA_kwCzR0hTQS13Z21mLXE5dnItdnd3Ns4AA_Bz
Source: GitHub Advisory Database
Origin: Unspecified
Severity: Moderate
Classification: General
Published: 9 days ago
Updated: 3 days ago

CVSS Score: 5.4
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Identifiers: GHSA-wgmf-q9vr-vww6, CVE-2024-45046
References:

• https://github.com/PHPOffice/PhpSpreadsheet/security/advisories/GHSA-wgmf-q9vr-vww6
• https://nvd.nist.gov/vuln/detail/CVE-2024-45046
• https://github.com/PHPOffice/PhpSpreadsheet/pull/3957
• https://github.com/PHPOffice/PhpSpreadsheet/commit/f7cf378faed2e11cf4825bf8bafea4922ae44667
• https://github.com/advisories/GHSA-wgmf-q9vr-vww6

Repository: https://github.com/PHPOffice/PhpSpreadsheet
Blast Radius: 23.2

Affected Packages