CVE-2026-108357

PhpSpreadsheet is a pure PHP library for reading and writing spreadsheet files. From 3.3.0 until 3.10.8 and 5.10.0, Reader\Xml passes stored SpreadsheetML XML through XmlScanner::scan in Xml::canRead and Xml::trySimpleXMLLoadStringPrivate, while Xml::unentity decodes numeric entities only after each DOCTYPE pattern check. A double-encoded less-than character is reduced by the first callback to another encoded character and by the second callback to a literal less-than sign, so SimpleXML receives an unchecked DOCTYPE and entity declaration. Processing attacker-controlled SpreadsheetML XML can cause entity-expansion denial of service and can permit local file access or SSRF on PHP before 8.0 or when LIBXML_NOENT is enabled. This issue is fixed in versions 3.10.8 and 5.10.0.

CVSS 4.0

8.8CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:L/SI:N/SA:N

EPSS

0.4% chance of exploitation in the next 30 days; higher than 29% of CVEs (scores of 2026-10-25)

CWEs

CWE-611, CWE-776

Published

2026-10-22

Modified

2026-10-23

Record from

the NVD, synced 2026-10-24

References

• https://github.com/PHPOffice/PhpSpreadsheet/commit/89f455c133e1a7e2d4abfadc43ce29eb7450d781
• https://github.com/PHPOffice/PhpSpreadsheet/commit/980b5c294493856f1a25754f1e8a1d2185b93738
• https://github.com/PHPOffice/PhpSpreadsheet/releases/tag/3.10.8
• https://github.com/PHPOffice/PhpSpreadsheet/releases/tag/5.10.0
• https://github.com/PHPOffice/PhpSpreadsheet/security/advisories/GHSA-rxj4-h86g-25gc

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