SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2019-12331

PHPOffice PhpSpreadsheet before 1.8.0 has an XXE issue.

HIGH 8.8EPSS 1.35%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.35%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 3.1
8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS
1.35% probability · 70th percentile
CISA KEV
Not listed
Weakness
CWE-611
Affected
phpoffice/phpspreadsheet
Source
cve@mitre.org

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.