URL Redirection to Untrusted Site ('Open Redirect')
An open redirect 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. By using backslashes in the `_failure_path` input field of login forms, an attacker can work around the redirection target restrictions and effectively redirect the user to any domain after login.
CWE-601 - Open Redirect
An open redirect attack employs a URL parameter, HTML refresh tags, or a DOM based location change to exploit the trust of a vulnerable domain to direct the users to a malicious website. The attack could lead to higher severity vulnerabilities such as unauthorized access control, account takeover, XSS, and more.