V-223355
SV-223355r961863_rule
CAT II
The Publish to Global Address List (GAL) button must be disabled in Outlook.
From: Microsoft Office 365 ProPlus Security Technical Implementation Guide (V3R5)
Description
<VulnDiscussion>This policy setting controls whether Outlook users can publish e-mail certificates to the Global Address List (GAL).
If you enable this policy setting, the "Publish to GAL" button does not display in the "E-mail Security" section of the Trust Center.
If you disable or do not configure this policy setting, Outlook users can publish their e-mail certificates to the GAL through the "E-mail Security" section of the Trust Center.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
Check Procedure
Verify the policy value for User Configuration >> Administrative Templates >> Microsoft Outlook 2016 >> Security >> Cryptography >> Do not display 'Publish to GAL' button is set to "Enabled".
Use the Windows Registry to navigate to the following key:
HKCU\software\policies\microsoft\office\16.0\outlook\security
If the value for publishtogaldisabled is REG_DWORD = 1, this is not a finding.
Fix Text
Set the policy value for User Configuration >> Administrative Templates >> Microsoft Outlook 2016 >> Security >> Cryptography >> Do not display 'Publish to GAL' button to "Enabled".
CCI Reference
CCI-000366- Created
- 2026-01-14 17:55:45
- Last Updated
- 2026-04-07 20:09:05