CVE-2026-40863: PhpSpreadsheet has CPU Denial of Service via Unbounded Row Index in SpreadsheetML XML Reader

high Affects phpoffice/phpspreadsheet. Feed 2026.10.29.1, updated 2026-10-28; published 2026-04-29; advisory modified 2026-10-26.

PhpSpreadsheet has CPU Denial of Service via Unbounded Row Index in SpreadsheetML XML Reader

Package: phpoffice/phpspreadsheet Composer
Affected versions: >=4.0.0 and <5.7.0 or >=3.3.0 and <3.10.5 or >=2.2.0 and <2.4.5 or >=2.0.0 and <2.1.16 or <1.30.6
Fixed in: 5.7.0, 3.10.5, 2.4.5, 2.1.16, 1.30.6
Severity: high CVSS 7.5
Exploitation: not on CISA KEV · EPSS 0% (33.6th percentile)
Published: 2026-04-29
Source: osv.dev

References

CWE-400 CWE-770

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