Title

Unsafe file types must be prevented from being attached to InfoPath forms. (Cat II impact)

Discussion

Users can attach any type of file to forms except potentially unsafe files that might contain viruses, such as .bat or .exe files. For the full list of file types that InfoPath disallows by default, see "Security Details" in Insert a file attachment control on the Microsoft Office Online website. If unsafe file types are added to InfoPath forms, they might be used as a means of attacking the computer on which the form is opened. These unsafe file types may include active content, or may introduce other vulnerabilities that an attacker can exploit.

Check Content

The policy value for User Configuration -> Administrative Templates -> Microsoft InfoPath 2013 -> Security -> "Prevent users from allowing unsafe file types to be attached to forms" must be set to "Enabled". Procedure: Use the Windows Registry Editor to navigate to the following key: HKCU\Software\Policies\Microsoft\Office\15.0\InfoPath\security Criteria: If the value DisallowAttachmentCustomization is REG_DWORD = 1, this is not a finding.

Fix Text

Set the policy value for User Configuration -> Administrative Templates -> Microsoft InfoPath 2013 -> Security -> "Prevent users from allowing unsafe file types to be attached to forms" to "Enabled".

Additional Identifiers

Rule ID: SV-53355r1_rule

Vulnerability ID: V-17764

Group Title: DTOO160 - Unsafe File Attachments in InfoPath

Expert Comments

CCIs tied to check.

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