Exposure of Sensitive Information to an Unauthorized Actor
The convenience initializer in the Multipeer Connectivity component in Apple iOS before 9 does not require an encrypted session, which allows local users to obtain cleartext multipeer data via an encrypted-to-unencrypted downgrade attack.
CWE-200 - Information Exposure
An information exposure vulnerability is categorized as an information flow (IF) weakness, which can potentially allow unauthorized access to otherwise classified information in the application, such as confidential personal information (demographics, financials, health records, etc.), business secrets, and the application's internal environment.