Exposure of Sensitive Information to an Unauthorized Actor
Mozilla Firefox before 42.0, when NTLM v1 is enabled for HTTP authentication, allows remote attackers to obtain sensitive hostname information by constructing a crafted web site that sends an NTLM request and reads the Workstation field of an NTLM type 3 message.
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.