2 min read
Microsoft 365 is the backbone of business productivity, but it also remains one of the most heavily exploited attack surfaces. Business email compromise, malicious macros, and unverified add-ins continue to slip past blunt defenses, leaving organizations stuck between two bad choices: block features and disrupt workflows, or accept the risks and rack up audit findings.
This trade-off feels familiar to most IT and security leaders. On one side is productivity; on the other is risk exposure. Neither is acceptable for long.
It doesn’t have to be this way. The real fix is simple in principle—only trust what your organization signs, and make signing routine. The challenge has always been execution at scale. That’s where Cryptomathic CrystalKey 360 (CK360) changes the equation.
When Blocking Features Becomes the Weakest Control
Business email compromise, macro abuse, and unvetted add-ins remain some of the most effective attack vectors in Microsoft 365. Most organizations still fall back on blunt controls: disable features, accept the productivity hit, and live with policy drift that auditors continue to flag.
It’s a cycle: disable, disrupt, drift, repeat. And each cycle leaves users frustrated, teams slowed down, and compliance gaps wide open.
The better goal is straightforward: only trust what your organization signs, and make signing routine. The barrier has always been scale. Issuing and protecting identities, renewing them on time, and wiring trust across Office without disrupting daily work is where most programs stall.
CK360: Turning Scale Into an Asset
CK360 makes scale attainable. It provides the missing governance layer: issuing, protecting, and auditing private key use for people and systems. With its crypto provider, keys remain non-exportable and under centralized control, while Office and Outlook behave as if the certificates were local. The trust model stays native, and users stay inside the tools they already know.
In other words: CK360 does the heavy lifting in the background, so users keep working in Outlook, Excel, and Word without noticing the change—except that everything simply works.
Why the Window Just Opened
Two shifts make this practical today. First, endpoint management has matured. Intune and Group Policy can reliably place certificates, trusted publishers, and Office settings on the right endpoints without constant firefighting. Second, Office and Outlook already trust the Windows certificate store through CAPI and CNG for S/MIME, macro signatures, VSTO manifests, ClickOnce, and even most PDF tools. If you can govern identities at scale, the built-in trust plane does the heavy lifting.
The Trust Plane in Motion
The model is simple but strict. CK360 crypto providers reroute signing and/or encryption request (e.g. for S/MIME or code signing) to the CrystalKey 360 back-end and HSMs. Keys are generated under CK360 control and never leave its boundary. Windows sees a standard certificate in the local store, but every private key operation is governed and logged.
This means every action is both transparent to the user and visible to auditors—a balance that has historically been difficult to achieve.
Intune or Group Policy distributes trust anchors and enforces policies: selected cohorts sign mail by default, macro settings block unsigned code, and access to the VBA project object model is limited to development workstations.
Business macros keep running once signed with a CK360-anchored key management layer. Internal add-ins, VSTO, and ClickOnce packages install seamlessly once signed in a controlled pipeline. PDF signing uses the same trust plane with corporate timestamping and reliable OCSP or CRL checks for long-term validation.
From Chaos to Repeatable Outcomes
The outcomes are tangible. Signed mail becomes the norm for executive, finance, legal, and procurement cohorts. Macro control gains precision: trusted spreadsheets continue to run, untrusted ones do not. Unsigned add-ins never launch, which stabilizes behavior.
Operational drag falls as enrollment, renewal, rotation, and deprovisioning follow a repeatable lifecycle. Helpdesk volume drops, particularly around S/MIME use and macro exceptions. Audit findings close themselves as trust anchors and policies become automated.
Put simply: CK360 replaces chaos with consistency. What used to require constant firefighting becomes a background process you can rely on.
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Please contact us to get a demo and see by yourself how easy it is to elevate the security posture of your standard Office suite with Cryptomathic CrystalKey 360.
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