CVE-2026-34084

Critical

Description

PhpSpreadsheet is a library for reading and writing spreadsheet files. In versions 1.30.2 and earlier, 2.0.0 through 2.1.14, 2.2.0 through 2.4.3, 3.3.0 through 3.10.3, and 4.0.0 through 5.5.0, when the filename argument to IOFactory::load() is user-controlled, an attacker can supply a PHP stream wrapper path (such as phar://, ftp://, or ssh2.sftp://) that passes the is_file() check in File::assertFile(). The phar:// wrapper triggers deserialization of the PHAR metadata, which can lead to remote code execution if a suitable gadget chain is available in the application. The ftp:// and ssh2.sftp:// wrappers can be used for server-side request forgery. This issue has been fixed in versions 1.30.3, 2.1.15, 2.4.4, 3.10.4, and 5.6.0.

SeverityCritical
CVSS9.8
Exploit probability—
ProductPhpoffice Phpspreadsheet
PublishedMay 5, 2026
First seenMay 5, 2026

How to fix

Update
  • phpoffice phpspreadsheet1.30.3, 2.1.15, 2.4.4, 3.10.4, 5.6.0 or later
  • phpoffice/phpspreadsheet5.6.0, 3.10.4, 2.4.4, 2.1.15, 1.30.3 or later

Affected products

ProductAffected versionsFixed in
phpoffice phpspreadsheetv < 1.30.3, 2.0.0 ≤ v < 2.1.15, 2.2.0 ≤ v < 2.4.4, 3.3.0 ≤ v < 3.10.4, 4.0.0 ≤ v < 5.6.01.30.3, 2.1.15, 2.4.4, 3.10.4, 5.6.0
phpoffice/phpspreadsheetPackagist4.0.0 ≤ v < 5.6.0, 3.3.0 ≤ v < 3.10.4, 2.2.0 ≤ v < 2.4.4, 2.0.0 ≤ v < 2.1.15, v < 1.30.35.6.0, 3.10.4, 2.4.4, 2.1.15, 1.30.3

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