Title

The BlackBerry Enterprise Mobility Server (BEMS) must remove all export ciphers to protect the confidentiality and integrity of transmitted information. (Cat II impact)

Discussion

During the initial setup of a Transport Layer Security (TLS) connection to the application server, the client sends a list of supported cipher suites in order of preference. The application server will reply with the cipher suite it will use for communication from the client list. If an attacker can intercept the submission of cipher suites to the application server and place, as the preferred cipher suite, a weak export suite, the encryption used for the session becomes easy for the attacker to break, often within minutes to hours.

Check Content

Verify BEMS has been configured to remove all export ciphers: 1. Find the xml file "jetty.xml" located in the BEMS install directory on the BEMS host Windows server. 2. Find the "AllowCiphersSuites" field. 3. Verify if any export ciphers are listed in the "jetty.xml" file. Verify only approved cypher suites are included. (See NIST SP 800-53r2 for a list of approved TLS suites.) If BEMS has been configured to use export ciphers, this is a finding.

Fix Text

Configure BEMS to remove all export ciphers. 1. Find the xml file "jetty.xml" located in the BEMS install directory on the BEMS host Windows server. 2. Find the "AllowCiphersSuites" field and remove all cipher suites that are not approved. (See NIST SP 800-53r2 for a list of approved TLS suites.) 3. Save file. 4. Restart the BEMS server.

Additional Identifiers

Rule ID: SV-93723r2_rule

Vulnerability ID: V-79017

Group Title: SRG-APP-000439-AS-000274

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.