Cross-Site Request Forgery (CSRF)
An issue was discovered in the Security component in Symfony 2.7.0 before 2.7.48, 2.8.x before 2.8.41, 3.x.x before 3.3.17, 3.4.x before 3.4.11, 4.0.x before 4.0.11, v4.1.0-BETA1 and v4.1.0-BETA2. By default, a user's session is invalidated when the user is logged out. This behavior can be disabled through the invalidate_session option. In this case, CSRF tokens were not erased during logout which allowed for CSRF token fixation.
CWE-352 - Cross-Site Request Forgery (CSRF)
Cross-Site Request Forgery (CSRF) is a vulnerability that allows an attacker to make arbitrary requests in an authenticated vulnerable web application and disrupt the integrity of the victim’s session. The impact of a successful CSRF attack may range from minor to severe, depending upon the capabilities exposed by the vulnerable application and privileges of the user. An attacker may force the user to perform state-changing requests like transferring funds, changing their email address or password etc. However, if an administrative level account is affected, it may compromise the whole web application and associated sensitive data.