Google Calendar Exposure Scanner

Google Calendar is a time-management and scheduling service developed by Google. It is used by millions of individuals and organizations worldwide to schedule meetings, set reminders, and coordinate events. By providing seamless integration with other Google services, it helps users stay organized both professionally and personally. Organizations often utilize Google Calendar to manage shared resources and schedules. Access to these calendars can be controlled through sharing settings, which allows organizations to maintain privacy and security. However, if improperly configured, these calendars can become publicly accessible, leading to potential exposure of sensitive information.

The exposure vulnerability in Google Calendar occurs when calendars are publicly accessible and embedded on external sites. This can occur due to improper configuration, specifically if users or organizations share their calendar URLs publicly. Publicly accessible calendars can inadvertently expose sensitive information such as meeting details, attendee names, event schedules, and other internal organizational data. Such exposure could pose privacy risks and lead to unauthorized access or targeted phishing attacks. Ensuring proper access settings is critical to maintaining the confidentiality of shared information.

Technical details of this exposure center around the sharing links used in Google Calendar, which, when improperly shared, make the calendars available for public viewing. The vulnerable endpoint can be identified by specific calendar URLs, such as those that include 'calendar.google.com/calendar/embed' or 'calendar.google.com/calendar/ical'. The template scans for these patterns in HTTP responses, indicating potential exposure. Users need to check the visibility settings in their calendar to ensure these are set to private or accessible to authorized personnel only.

If exploited by malicious actors, the exposure could lead to several negative effects. Sensitive meeting and schedule information could be obtained and misused, potentially harming individual privacy or organizational security. The data might be used in targeted attacks, such as phishing or social engineering, to extract more sensitive information. An exposed calendar could lead to unauthorized access to organization routines or confidential discussions, compounding the potential for data leaks or operational disruptions.

REFERENCES

• https://support.google.com/calendar/answer/37083