PHPSpreadsheet is a pure PHP library for reading and writing spreadsheet files. The security scanner responsible for preventing XXE attacks in the XLSX reader can be bypassed by slightly modifying the XML structure, utilizing white-spaces. On servers that allow users to upload their own Excel (XLSX) sheets, Server files and sensitive information can be disclosed by providing a crafted sheet. The security scan function in src/PhpSpreadsheet/Reader/Security/XmlScanner.php contains a flawed XML encoding check to retrieve the input file's XML encoding in the toUtf8 function. The function searches for the XML encoding through a defined regex which looks for `encoding="*"` and/or `encoding='*'`, if not found, it defaults to the UTF-8 encoding which bypasses the conversion logic. This logic can be used to pass a UTF-7 encoded XXE payload, by utilizing a whitespace before or after the = in the attribute definition. Sensitive information disclosure through the XXE on sites that allow users to upload their own excel spreadsheets, and parse them using PHPSpreadsheet's Excel parser. This issue has been addressed in release versions 1.29.1, 2.1.1, and 2.3.0. All users are advised to upgrade. There are no known workarounds for this vulnerability.
History

Mon, 07 Oct 2024 21:15:00 +0000

Type Values Removed Values Added
First Time appeared Phpoffice
Phpoffice phpspreadsheet
CPEs cpe:2.3:a:phpoffice:phpspreadsheet:*:*:*:*:*:*:*:*
Vendors & Products Phpoffice
Phpoffice phpspreadsheet
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Mon, 07 Oct 2024 20:15:00 +0000

Type Values Removed Values Added
Description PHPSpreadsheet is a pure PHP library for reading and writing spreadsheet files. The security scanner responsible for preventing XXE attacks in the XLSX reader can be bypassed by slightly modifying the XML structure, utilizing white-spaces. On servers that allow users to upload their own Excel (XLSX) sheets, Server files and sensitive information can be disclosed by providing a crafted sheet. The security scan function in src/PhpSpreadsheet/Reader/Security/XmlScanner.php contains a flawed XML encoding check to retrieve the input file's XML encoding in the toUtf8 function. The function searches for the XML encoding through a defined regex which looks for `encoding="*"` and/or `encoding='*'`, if not found, it defaults to the UTF-8 encoding which bypasses the conversion logic. This logic can be used to pass a UTF-7 encoded XXE payload, by utilizing a whitespace before or after the = in the attribute definition. Sensitive information disclosure through the XXE on sites that allow users to upload their own excel spreadsheets, and parse them using PHPSpreadsheet's Excel parser. This issue has been addressed in release versions 1.29.1, 2.1.1, and 2.3.0. All users are advised to upgrade. There are no known workarounds for this vulnerability.
Title XML External Entity Reference (XXE) in PHPSpreadsheet's XLSX reader
Weaknesses CWE-611
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2024-10-07T20:03:27.080Z

Updated: 2024-10-07T20:25:10.635Z

Reserved: 2024-08-26T18:25:35.442Z

Link: CVE-2024-45293

cve-icon Vulnrichment

Updated: 2024-10-07T20:25:03.532Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2024-10-07T20:15:06.100

Modified: 2024-10-10T12:57:21.987

Link: CVE-2024-45293

cve-icon Redhat

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