SB2018121906 - Multiple vulnerabilities in Symfony

Description

This security bulletin contains information about 2 secuirty vulnerabilities.

1) Improper input validation (CVE-ID: CVE-2018-19789)

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to an error 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 A remote unauthenticated attacker can submit a file upload to the corresponding field instead of a normal text input, call `UploadedFile::__toString()` which will then return and disclose the path of the uploaded file. If combined with a local file inclusion issue in certain circumstances a remote attacker can execute arbitrary code with elevated privileges.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

2) Open redirect (CVE-ID: CVE-2018-19790)

The vulnerability allows a remote unauthenticated attacker to redirect the target user to external websites.

The weakness exists due to improper sanitization of user-supplied data. A remote attacker can use backslashes in the `_failure_path` input field of login forms, work around the redirection target restrictions and effectively redirect the user to any domain after login.

Remediation

Install update from vendor's website.

References

• https://symfony.com/blog/cve-2018-19789-disclosure-of-uploaded-files-full-path
• https://symfony.com/blog/cve-2018-19790-open-redirect-vulnerability-when-using-security-http