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CVE-2026-40902
HIGH · CVSS 7.5
EPSS exploitation probability: 0%
Published 2026-05-12T22:16:33.923 · Last modified 2026-06-17T10:45:51.377

Summary

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 XLSX reader's ColumnAndRowAttributes::readRowAttributes() method reads row numbers from XML attributes without validating them against the spreadsheet maximum row limit (AddressRange::MAX_ROW = 1,048,576). An attacker can craft a minimal XLSX file (~1.6KB) containing a <row r="999999999"/> element that inflates cachedHighestRow to 999,999,999, causing any subsequent row iteration to attempt ~1 billion loop cycles and exhaust CPU resources. This vulnerability is fixed in 1.30.4, 2.1.16, 2.4.5, 3.10.5, and 5.7.0.

Affected products

phpoffice — phpspreadsheet

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.