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.
http://www.securityfocus.com/bid/106249
https://lists.debian.org/debian-lts-announce/2019/03/msg00009.html
https://seclists.org/bugtraq/2019/May/21
https://symfony.com/blog/cve-2018-19790-open-redirect-vulnerability-when-using-security-http
Source: MITRE
Published: 2018-12-18
Updated: 2019-05-10
Type: CWE-601
Base Score: 5.8
Vector: AV:N/AC:M/Au:N/C:P/I:P/A:N
Impact Score: 4.9
Exploitability Score: 8.6
Severity: MEDIUM
Base Score: 6.1
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Impact Score: 2.7
Exploitability Score: 2.8
Severity: MEDIUM