CVE-2026-40863

Published: Mag 13, 2026 Last Modified: Mag 13, 2026
ExploitDB:
Other exploit source:
Google Dorks:
HIGH 7,5
Source: [email protected]
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: none
Scope: unchanged
Confidentiality: none
Integrity: none
Availability: high

Description

AI Translation Available

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 <Row> 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.

770

Allocation of Resources Without Limits or Throttling

Incomplete
Abstraction: Base Structure: Simple
Common Consequences
Security Scopes Affected:
Availability
Potential Impacts:
Dos: Resource Consumption (Cpu) Dos: Resource Consumption (Memory) Dos: Resource Consumption (Other)
Applicable Platforms
All platforms may be affected
Likelihood of Exploit: High
View CWE Details
https://github.com/PHPOffice/PhpSpreadsheet/security/adviso…
https://github.com/PHPOffice/PhpSpreadsheet/security/advisories/GHSA-84wq-86v6-…