Exposure of Sensitive Information to an Unauthorized Actor
pfSense before 2.1.4, when HTTP is used, does not include the HTTPOnly flag in a Set-Cookie header for the session cookie, which makes it easier for remote attackers to obtain potentially sensitive information via script access to this cookie.
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.