CVE-2026-40863: PhpSpreadsheet is a pure PHP library for reading and writing spreadsheet files. Prior to 1.30.4, 2.1.16, 2.4.5, 3.10.5, and 5.7.0, the SpreadsheetML XML reader…

PriorityP341high7.5CVSS 3.1

AVNACLPRNUINSUCNINAH

EPSS

0.40%

31.4th percentile

PhpSpreadsheet is a pure PHP library for reading and writing spreadsheet files. Prior to 1.30.4, 2.1.16, 2.4.5, 3.10.5, and 5.7.0, the SpreadsheetML XML reader (Reader\Xml) does not validate the ss:Index row attribute against the maximum allowed row count (AddressRange::MAX_ROW = 1,048,576). An attacker can craft a SpreadsheetML XML file with ss:Index="999999999" on a element, which inflates the internal cachedHighestRow to ~1 billion. Any subsequent call to getRowIterator() without an explicit end row will attempt to iterate ~1 billion rows, causing CPU exhaustion and denial of service. This vulnerability is fixed in 1.30.4, 2.1.16, 2.4.5, 3.10.5, and 5.7.0.

Affected

14 ranges

Vendor	Product	Version range	Fixed in
phpoffice	phpspreadsheet	< 1.30.4	1.30.4
phpoffice	phpspreadsheet	—	—
phpoffice	phpspreadsheet	—	—
phpoffice	phpspreadsheet	—	—
phpoffice	phpspreadsheet	—	—
phpoffice	phpspreadsheet	>= 0 < 1.30.4	1.30.4
phpoffice	phpspreadsheet	>= 2.0.0 < 2.1.16	2.1.16
phpoffice	phpspreadsheet	>= 2.0.0 < 2.1.16	2.1.16
phpoffice	phpspreadsheet	>= 2.2.0 < 2.4.5	2.4.5
phpoffice	phpspreadsheet	>= 2.2.0 < 2.4.5	2.4.5
phpoffice	phpspreadsheet	>= 3.3.0 < 3.10.5	3.10.5
phpoffice	phpspreadsheet	>= 3.3.0 < 3.10.5	3.10.5
phpoffice	phpspreadsheet	>= 4.0.0 < 5.7.0	5.7.0
phpoffice	phpspreadsheet	>= 4.0.0 < 5.7.0	5.7.0

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