Arbitrary file upload in Sensiolabs Symfony

CVE-2018-19789

An issue was discovered in Symfony 2.7.x before 2.7.50, 2.8.x before 2.8.49, 3.x before 3.4.20, 4.0.x before 4.0.15, 4.1.x before 4.1.9, and 4.2.x before 4.2.1. When using the scalar type hint `string` in a setter method (e.g. `setName(string $name)`) of a class that's the `data_class` of a form, and when a file upload is submitted to the corresponding field instead of a normal text input, then `UploadedFile::__toString()` is called which will then return and disclose the path of the uploaded file. If combined with a local file inclusion issue in certain circumstances this could escalate it to a Remote Code Execution.

Vulnerability class: Unrestricted File Upload

EPSS: 0.036 (88.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2018-19789?
CVE-2018-19789 is a medium-severity vulnerability in Sensiolabs Symfony, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 5.3/10. Published 2018-12-18.
How severe is CVE-2018-19789?
Medium severity. CVSS v3 base score is 5.3 out of 10.