phpoffice/phpspreadsheet · Security
XXE in PHPSpreadsheet due to incomplete fix for previous encoding issue
- GHSA ID
- GHSA-vvwv-h69m-wg6f
- CVE ID
- CVE-2019-12331
- Severity
- high
- Published
- Updated
- CVSS
- 8.8 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- CVSS v3
- 8.8 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Description
PHPOffice PhpSpreadsheet before 1.8.0 has an XXE issue. The XmlScanner decodes the sheet1.xml from an .xlsx to utf-8 if something else than UTF-8 is declared in the header. This was a security measurement to prevent CVE-2018-19277 but the fix is not sufficient. By double-encoding the the xml payload to utf-7 it is possible to bypass the check for the string ?<!ENTITY? and thus allowing for an xml external entity processing (XXE) attack.
CWEs
- CWE-611 · Improper Restriction of XML External Entity Reference
References
- https://nvd.nist.gov/vuln/detail/CVE-2019-12331 ↗
- https://github.com/PHPOffice/PhpSpreadsheet/blob/master/CHANGELOG.md#180---2019-07-01 ↗
- https://github.com/PHPOffice/PhpSpreadsheet/releases/tag/1.8.0 ↗
- https://github.com/PHPOffice/PhpSpreadsheet/pull/1041 ↗
- https://github.com/PHPOffice/PhpSpreadsheet/commit/0e6238c69e863b58aeece61e48ea032696c6dccd ↗
- https://github.com/FriendsOfPHP/security-advisories/blob/master/phpoffice/phpspreadsheet/CVE-2019-12331.yaml ↗
- https://herolab.usd.de/security-advisories/usd-2019-0046 ↗
- https://github.com/advisories/GHSA-vvwv-h69m-wg6f ↗