CVE-2024-48917
The `XmlScanner` class has a scan method which should prevent XXE attacks.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.73%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
PhpSpreadsheet is a PHP library for reading and writing spreadsheet files. The `XmlScanner` class has a scan method which should prevent XXE attacks. However, in a bypass of the previously reported `CVE-2024-47873`, the regexes from the `findCharSet` method, which is used for determining the current encoding can be bypassed by using a payload in the encoding UTF-7, and adding at end of the file a comment with the value `encoding="UTF-8"` with `"`, which is matched by the first regex, so that `encoding='UTF-7'` with single quotes `'` in the XML header is not matched by the second regex. An attacker can bypass the sanitizer and achieve an XML external entity attack. Versions 1.9.4, 2.1.3, 2.3.2, and 3.4.0 fix the issue.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- EPSS
- 0.73% probability · 52th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-611
- Affected
- phpoffice/phpspreadsheet
- Source
- security-advisories@github.com
References
- https://github.com/PHPOffice/PhpSpreadsheet/blob/39fc51309181e82593b06e2fa8e45ef8333a0335/src/PhpSpreadsheet/Reader/Security/XmlScanner.phpProduct
- https://github.com/PHPOffice/PhpSpreadsheet/security/advisories/GHSA-7cc9-j4mv-vcjpExploit, Vendor Advisory
- https://owasp.org/www-community/vulnerabilities/XML_External_Entity_(XXE)_ProcessingNot Applicable
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.