cis-gworkspace-3-1-1-2-1

name	cis-gworkspace-3.1.1.2.1
description	Ensure external sharing options for secondary calendars are configured
category	cis-gworkspace
version	1.3.0
author	cyberstrike-official
tags	["cis","gcp","google-workspace","calendar","sharing","external-sharing","offline"]
cis_id	3.1.1.2.1
cis_benchmark	CIS Google Workspace Foundations Benchmark v1.3.0
tech_stack	["gcp","google-workspace"]
cwe_ids	[]
chains_with	[]
prerequisites	[]
severity_boost	{}

3.1.1.2.1 Ensure external sharing options for secondary calendars are configured (Manual)

Description

Control how much calendar information users in your organization can share externally.

Rationale

Prevent data leakage by restricting the amount of information is externally viewable when a user shares their calendar with someone external to your organization.

Impact

• Once you limit external sharing for your organization, users can't exceed these limits when sharing individual events. For example, if you limit your organization's external sharing to Free/Busy, events with Public visibility are only shared as Free/Busy.
• External mobile users who previously synced events may keep seeing restricted details. That access stops when their device is wiped and re-synced.
• If you lower the external sharing level, people outside your organization may lose access to calendars they could previously see.

Audit Procedure

To verify this setting via the Google Workspace Admin Console:

1. Log in to https://admin.google.com as an administrator
2. Select Apps
3. Select Google Workspace
4. Select Calendar
5. Under General settings, select External sharing options for secondary calendars
6. Ensure Only free/busy information (hide event details) is selected

Expected Result

Only free/busy information (hide event details) should be selected for external sharing options for secondary calendars.

Remediation

To configure this setting via the Google Workspace Admin Console:

1. Log in to https://admin.google.com as an administrator
2. Select Apps
3. Select Google Workspace
4. Select Calendar
5. Under General settings, select External sharing options for secondary calendars
6. Select Only free/busy information (hide event details)
7. Select Save

Default Value

External sharing options for secondary calendars is Share all information, but outsiders cannot change calendars

References

• https://support.google.com/a/answer/60765