PHPOffice PhpSpreadsheet up to 5.6.x XML File getRowIterator allocation of resources

Summaryinfo

A vulnerability marked as problematic has been reported in PHPOffice PhpSpreadsheet up to 1.30.3/2.1.15/2.4.4/3.10.4/5.6.x. This affects the function getRowIterator of the component XML File Handler. The manipulation leads to allocation of resources. This vulnerability is uniquely identified as CVE-2026-40863. The attack is possible to be carried out remotely. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in PHPOffice PhpSpreadsheet up to 1.30.3/2.1.15/2.4.4/3.10.4/5.6.x. It has been rated as problematic. This issue affects the function getRowIterator of the component XML File Handler. The manipulation with an unknown input leads to a allocation of resources vulnerability. Using CWE to declare the problem leads to CWE-770. The product allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor. Impacted is availability. The summary by CVE is:

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.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-40863 since 04/15/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

Upgrading to version 1.30.4, 2.1.16, 2.4.5, 3.10.5 or 5.7.0 eliminates this vulnerability.

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Productinfo

Vendor

• PHPOffice

Name

• PhpSpreadsheet

Version

• 1.30.0
• 1.30.1
• 1.30.2
• 1.30.3
• 2.1.0
• 2.1.1
• 2.1.2
• 2.1.3
• 2.1.4
• 2.1.5
• 2.1.6
• 2.1.7
• 2.1.8
• 2.1.9
• 2.1.10
• 2.1.11
• 2.1.12
• 2.1.13
• 2.1.14
• 2.1.15
• 2.4.0
• 2.4.1
• 2.4.2
• 2.4.3
• 2.4.4
• 3.10.0
• 3.10.1
• 3.10.2
• 3.10.3
• 3.10.4
• 5.0
• 5.1
• 5.2
• 5.3
• 5.4
• 5.5
• 5.6

Website

• Product: https://github.com/PHPOffice/PhpSpreadsheet/

CPE 2.3info

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CPE 2.2info

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Entryinfo

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