An ftp:// transfer configured with CURLUSESSL_NONE can reuse a pooled FTP
control connection that a previous easy handle upgraded with STARTTLS and
authenticated using a client certificate. The second handle performs neither a
new TLS handshake nor a new FTP login, so the server continues to authorize it
under the first handles certificate identity.
Weakness
The product does not sufficiently enforce boundaries between the states of different sessions, causing data to be provided to, or used by, the wrong session.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Red Hat Hardened Images | RedHat | curl-main-8.23.0-0.1.hum1 | * |
| Curl | Ubuntu | upstream | * |
Extended Description
Data can “bleed” from one session to another through member variables of singleton objects, such as Servlets, and objects from a shared pool. In the case of Servlets, developers sometimes do not understand that, unless a Servlet implements the SingleThreadModel interface, the Servlet is a singleton; there is only one instance of the Servlet, and that single instance is used and re-used to handle multiple requests that are processed simultaneously by different threads. A common result is that developers use Servlet member fields in such a way that one user may inadvertently see another user’s data. In other words, storing user data in Servlet member fields introduces a data access race condition.