Spring Security versions 5.4.0 to 5.4.3, 5.3.0.RELEASE to 5.3.8.RELEASE, 5.2.0.RELEASE to 5.2.8.RELEASE, and older unsupported versions can fail to save the SecurityContext if it is changed more than once in a single request. The SecurityContext can fail to save to the HttpSession if a developer changes the SecurityContext twice in a single request when both of the following conditions are met: First the developer must change the SecurityContext before the HttpResponse is committed and then the HttpResponse must be committed before the SecurityContextPersistenceFilter completes. Then the developer must attempt to change the SecurityContext again before the SecurityContextPersistenceFilter completes. A malicious user cannot cause the bug to happen (it must be programmed in). However, if the application's intent is to only allow the user to run with elevated privileges in a small portion of the application, the bug can be leveraged to extend those privileges to the rest of the application.