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cve.new
GHSA-wgmf-q9vr-vww6medium5.4

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

Check your stack

The advisory, in context

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.

Affected packages

Start with the recorded fix for your release branch. Check your installed version and test compatibility before upgrading. Fixing this advisory does not rule out other vulnerabilities in the release.

Ecosystem versions

From 2.0.0 before 2.1.0

Fixed in 2.1.0

1 explicitly affected versions

2.0.0

View affected-version evidence
{
  "ranges": [
    {
      "events": [
        {
          "introduced": "2.0.0"
        },
        {
          "fixed": "2.1.0"
        }
      ],
      "type": "ECOSYSTEM"
    }
  ],
  "versions": [
    "2.0.0"
  ]
}
Ecosystem versions

Earlier releases before 1.29.1

Fixed in 1.29.1

46 explicitly affected versions

1.0.0, 1.0.0-beta, 1.0.0-beta2, 1.1.0, 1.10.0, 1.10.1, 1.11.0, 1.12.0, 1.13.0, 1.14.0, 1.14.1, 1.15.0, 1.16.0, 1.17.0, 1.17.1, 1.18.0, 1.19.0, 1.2.0, 1.2.1, 1.20.0, 1.21.0, 1.22.0, 1.23.0, 1.24.0, 1.24.1, 1.25.0, 1.25.1, 1.25.2, 1.26.0, 1.27.0, 1.27.1, 1.28.0, 1.29.0, 1.3.0, 1.3.1, 1.4.0, 1.4.1, 1.5.0, 1.5.1, 1.5.2, 1.6.0, 1.7.0, 1.8.0, 1.8.1, 1.8.2, 1.9.0

View affected-version evidence
{
  "ranges": [
    {
      "events": [
        {
          "introduced": "0"
        },
        {
          "fixed": "1.29.1"
        }
      ],
      "type": "ECOSYSTEM"
    }
  ],
  "versions": [
    "1.0.0",
    "1.0.0-beta",
    "1.0.0-beta2",
    "1.1.0",
    "1.10.0",
    "1.10.1",
    "1.11.0",
    "1.12.0",
    "1.13.0",
    "1.14.0",
    "1.14.1",
    "1.15.0",
    "1.16.0",
    "1.17.0",
    "1.17.1",
    "1.18.0",
    "1.19.0",
    "1.2.0",
    "1.2.1",
    "1.20.0",
    "1.21.0",
    "1.22.0",
    "1.23.0",
    "1.24.0",
    "1.24.1",
    "1.25.0",
    "1.25.1",
    "1.25.2",
    "1.26.0",
    "1.27.0",
    "1.27.1",
    "1.28.0",
    "1.29.0",
    "1.3.0",
    "1.3.1",
    "1.4.0",
    "1.4.1",
    "1.5.0",
    "1.5.1",
    "1.5.2",
    "1.6.0",
    "1.7.0",
    "1.8.0",
    "1.8.1",
    "1.8.2",
    "1.9.0"
  ]
}
Ecosystem versions

Earlier releases through 1.8.2 (inclusive)

No fix recorded for this interval.

9 explicitly affected versions

1.7.9, 1.7.9-rc1, 1.8.0, 1.8.0rc1, 1.8.0rc2, 1.8.0rc3, 1.8.0rc4, 1.8.1, 1.8.2

View affected-version evidence
{
  "ranges": [
    {
      "events": [
        {
          "introduced": "0"
        },
        {
          "last_affected": "1.8.2"
        }
      ],
      "type": "ECOSYSTEM"
    }
  ],
  "versions": [
    "1.7.9",
    "1.7.9-rc1",
    "1.8.0",
    "1.8.0rc1",
    "1.8.0rc2",
    "1.8.0rc3",
    "1.8.0rc4",
    "1.8.1",
    "1.8.2"
  ]
}

References