Unauthenticated Privilege Escalation in CA 2E Web Option
CA 2E Web Option (r8.1.2) and potentially others, is vulnerable to unauthenticated privilege escalation via a predictable session token. The POST parameter session token W2E_SSNID appears as follows: W2E_SSNID=W90NIxGoSsN1023ZYW2E735182000013CLSpKfgkCJSLKsc600061JKenjKnEJuNX9GoVjCEbqIuKh6kFRvbzYnUxgQtONszJldyAar3LtTSwsmBLpdlPc5iDH4Zf75. However, this token is poorly validated, leading to W2E_SSNID=W90NIxGoSsN1023ZYW2E735182000013 being accepted as a valid session. By incrementing and decrementing the digits at the end of the value given above, it is possible to control the session at the given ID. This token is sent as part of the login page, and as such, can be manipulated by an unauthenticated attacker, giving them access to any valid session. Consequentially, it is possible to access the following page as such: https://app.domain.co.uk/web2edoc/close.htm?SSNID=W90NIxGoSsN1023ZYW2E735182000026 Ending the session specified, which could lead to a denial of service condition.