CVE-2026-35453

PhpSpreadsheet is a library for reading and writing spreadsheet files. In versions 1.30.3 and earlier, 2.0.0 through 2.1.15, 2.2.0 through 2.4.4, 3.3.0 through 3.10.4, and 4.0.0 through 5.6.0, the HTML Writer skips htmlspecialchars() output escaping when a cell uses a custom number format containing the @ text placeholder with additional literal text (e.g., @ "items"). The escaping is only applied when the formatted output strictly equals the original cell value. When the format code contains @ with quoted literal text, the formatter substitutes the raw cell value into the format string and returns early without invoking the escaping callback. An attacker who can control cell content in a spreadsheet processed by the HTML Writer can inject arbitrary HTML and JavaScript into the generated output. This issue has been fixed in versions 1.30.4, 2.1.16, 2.4.5, 3.10.5, and 5.7.0.
Configurations

Configuration 1 (hide)

OR cpe:2.3:a:phpoffice:phpspreadsheet:*:*:*:*:*:*:*:*
cpe:2.3:a:phpoffice:phpspreadsheet:*:*:*:*:*:*:*:*
cpe:2.3:a:phpoffice:phpspreadsheet:*:*:*:*:*:*:*:*
cpe:2.3:a:phpoffice:phpspreadsheet:*:*:*:*:*:*:*:*
cpe:2.3:a:phpoffice:phpspreadsheet:*:*:*:*:*:*:*:*

History

08 May 2026, 17:08

Type Values Removed Values Added
First Time Phpoffice phpspreadsheet
Phpoffice
CPE cpe:2.3:a:phpoffice:phpspreadsheet:*:*:*:*:*:*:*:*
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 5.4
References () https://github.com/PHPOffice/PhpSpreadsheet/security/advisories/GHSA-6wpp-88cp-7q68 - () https://github.com/PHPOffice/PhpSpreadsheet/security/advisories/GHSA-6wpp-88cp-7q68 - Exploit, Vendor Advisory

06 May 2026, 16:16

Type Values Removed Values Added
References () https://github.com/PHPOffice/PhpSpreadsheet/security/advisories/GHSA-6wpp-88cp-7q68 - () https://github.com/PHPOffice/PhpSpreadsheet/security/advisories/GHSA-6wpp-88cp-7q68 -

05 May 2026, 20:16

Type Values Removed Values Added
New CVE

Information

Published : 2026-05-05 20:16

Updated : 2026-05-08 17:08


NVD link : CVE-2026-35453

Mitre link : CVE-2026-35453

CVE.ORG link : CVE-2026-35453


JSON object : View

Products Affected

phpoffice

  • phpspreadsheet
CWE
CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')