CVE-2019-12331

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.

• CVE ID
• CVE-2019-12331

• Assigner
• cve@mitre.org

• Vulnerability Status
• Modified

• Published Version
• 2019-11-07T15:15:10

• Last Modified Date
• 2020-02-10T21:49:54

• Version
• 2.0

• Vector String
• AV:N/AC:M/Au:N/C:P/I:P/A:P

• Access Vector
• NETWORK

• Access Compatibility
• MEDIUM

• Authentication
• NONE

• Confidentiality Impact
• PARTIAL

• Integrity Impact
• PARTIAL

• Availability Impact
• PARTIAL

• Base Score
• 6.8

• Severity
• MEDIUM

• Exploitability Score
• 8.6

• Impact Score
• 6.4

• Version
• 3.1

• Vector String
• CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

• Attack Vector
• NETWORK

• Attack Compatibility
• LOW

• Privileges Required
• NONE

• User Interaction
• REQUIRED

• Scope
• UNCHANGED

• Confidentiality Impact
• HIGH

• Availability Impact
• HIGH

• Base Score
• 8.8

• Base Severity
• HIGH

• Exploitability Score
• 2.8

• Impact Score
• 5.9