Vulnerability Description
PhpSpreadsheet is a pure PHP library for reading and writing spreadsheet files. Prior to 1.30.7, 2.1.19, 2.4.8, 3.10.8, and 5.10.0, XmlScanner::scan in src/PhpSpreadsheet/Reader/Security/XmlScanner.php uses a DOCTYPE detection pattern that accounts for NUL-byte interleaving but not ISO-2022 escape sequences in XLSX XML parts. The escape sequences prevent the scanner from matching the declaration, and XML charset normalization then removes the escape bytes before parsing, exposing a valid DOCTYPE and entity definitions. Processing an attacker-controlled XLSX can therefore cause entity-expansion denial of service on supported PHP versions 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 1.30.7, 2.1.19, 2.4.8, 3.10.8, and 5.10.0.
Related Weaknesses (CWE)
References
- https://github.com/PHPOffice/PhpSpreadsheet/commit/299993894dce37aa3b64aa23e9a3f
- https://github.com/PHPOffice/PhpSpreadsheet/commit/89f455c133e1a7e2d4abfadc43ce2
- https://github.com/PHPOffice/PhpSpreadsheet/commit/980b5c294493856f1a25754f1e8a1
- https://github.com/PHPOffice/PhpSpreadsheet/commit/9a0b48622ebfe93fa48cb9bc09ce5
- https://github.com/PHPOffice/PhpSpreadsheet/commit/da13f40e8760d599b0e8a296017d4
- https://github.com/PHPOffice/PhpSpreadsheet/releases/tag/1.30.7
- https://github.com/PHPOffice/PhpSpreadsheet/releases/tag/2.1.19
- https://github.com/PHPOffice/PhpSpreadsheet/releases/tag/2.4.8
- 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-3x94-m842-9
FAQ
What is CVE-2026-108358?
CVE-2026-108358 is a documented vulnerability. PhpSpreadsheet is a pure PHP library for reading and writing spreadsheet files. Prior to 1.30.7, 2.1.19, 2.4.8, 3.10.8, and 5.10.0, XmlScanner::scan in src/PhpSpreadsheet/Reader/Security/XmlScanner.ph...
How severe is CVE-2026-108358?
CVSS scoring is not yet available for CVE-2026-108358. Check NVD for updates.
Is there a patch for CVE-2026-108358?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.