Cyber Due Diligence for CISOs

Protect the thesis, accelerate integration, and turn cyber risk into operating leverage.

If your company partners with private equity, growth equity, or engages in acquisitions and carve-outs, cyber due diligence is no longer an IT courtesy - it’s enterprise value assurance. As CISO, you’re carrying two levers the deal team can’t:

1. preventing negative surprises that re-price the asset and

2. enabling a clean, rapid Day-1/Day-100 integration. That requires evidence, not narratives; operating metrics, not slideware.

The Investment Lens You Need

Cyber diligence is operational diligence.
Identity, recovery, and vendor access determine how quickly you can stabilize the asset, shut down inherited risk, and capture synergies. Strong posture shortens transition services, prevents re-trades, and keeps revenue programs moving. Weak posture shows up as unplanned capex/opex, regulatory drag, churn, and slip in integration milestones.

How thin diligence destroys value.
When diligence is light, the pain spreads: IR and forensics burn budget, customer certifications stall, downtime becomes the headline cost, premiums rise while exclusions harden, engineering time diverts to emergency fixes, and Day-1/Day-90 objectives drift. Even without a headline incident, the catch-up - MFA, PAM, log retention, DR drills, vendor offboarding—hits post-close when the organization is least tolerant of disruption.

Translate findings into deal mechanics.
Your outputs should roll straight into the term sheet and the operating plan: quantified remediation → price chips or holdbacks; control-specific reps/warranties; a 100-day plan with board-visible milestones. Insurance bound to the actual control state, not aspirational policy. That’s how you cap downside and accelerate value creation.

What Real Maturity Looks Like

• Identity-first: Broad SSO; phishing-resistant MFA; device trust; automated JML; minimal standing privilege.

• Privileged access: JIT via PAM; approval workflow; session recording; break-glass audited.

• Endpoint & email: EDR ≥95% coverage; DMARC enforced; legacy mail protocols disabled; executive protection verified.

• Detect & respond: ≥12 months searchable logs; validated high-fidelity detections; 24×7 response with MTTR tracked and reported.

• Data protection: Classification for priority domains; DLP on egress; keys in KMS/HSM; backups immutable/segmented; restores practiced and timed.

• Third parties: Tiered by blast radius; SSO/MFA enforced for Tier-1; 15-minute kill-switch; contractual evidence rights; offboarding muscle memory.

• Delivery: Secrets out of code; dependency pinning; artifact signing; rollback rehearsed.

The 100-Day Integration Sprint (Playbook You Can Run Monday)

Days 0–30

• Enforce phishing-resistant MFA for all admins and remote access; revoke stale accounts; EDR to ≥95% coverage.

• Snapshot and lock backups; perform a timed restore of one crown-jewel workload; document RTO/RPO.

• Rank top 20 vendors by blast radius; enable SSO/MFA; stand up kill-switch playbooks.

Days 31–60

• Roll out PAM JIT with session recording; enable device posture for SaaS.

• DMARC to reject; disable IMAP/POP/legacy SMTP; harden CI/CD (secrets scanning, dependency pinning, artifact signing).

• Run a tabletop with CFO/COO/GC; close top detection gaps surfaced.

Days 61–100

• Classify priority data sets; turn on DLP for key egress paths; finalize breach-notice SLAs and evidence rights with Tier-1 vendors.

• DR exercise for a customer-facing service; publish tested RTO/RPO.

• Launch a board dashboard: identity health, coverage, MTTR, vendor blast radius, restore results.

Board Slide—One Page

• Objective: Preserve deal value, compress Day-1/Day-100 timelines, and reduce run-rate leakage.

• Signals We Track: MFA exceptions, admin count by name, EDR coverage, timed restore results, MTTR, Tier-1 vendor kill-switch readiness.

• Q3 Targets: PAM JIT live; DMARC=reject; ≥95% EDR; one crown-jewel DR drill complete; board dashboard established.

• Risks & Mitigations: Legacy access paths, shadow AI use, vendor sprawl → phased controls, contractual teeth, rapid offboarding drills.

• Ask: Approve holdback-tied milestones and budget gates aligned to the 100-day plan.

Leadership Talk-Track

• “We’re converting control posture into measurable business outcomes: faster stabilization, fewer surprises, tighter insurance, and shorter revenue disruption.”

• “Our proof points are operational—timed restores, admin lists by name, exception logs—not policies.”

• “Deal terms align incentives: milestone-based holdbacks, control-specific reps, and insurance bound to what we actually run.”

One-Page CISO Checklist

• Valuation/terms alignment: Quantified remediation mapped to price chips/holdbacks; control-specific reps/warranties drafted.

• Restore reality: Timed, successful restore (≤90 days) of a crown-jewel app/DB; RTO/RPO vs. customer SLAs.

• Identity health: IdP admin list by name; phishing-resistant MFA; automated JML; vendor/contractor SSO; minimal standing privilege.

• EDR/MDM coverage: ≥95% endpoints/servers; quarantine non-compliant; exportable coverage evidence.

• Email/Domain: Modern filtering; DMARC=reject; legacy protocols off; VIP protection validated.

• Logging/Response: ≥12-month searchable retention; validated detections; 24×7 response with MTTR tracked.

• AI risk posture: Inventory sanctioned/unsanctioned AI tools and plugins; access boundaries; remediation plan for shadow AI.

• Data & keys: Classification for priority domains; DLP on egress; keys in KMS/HSM; backups immutable and segmented.

• Third parties: Tiered by blast radius; SSO/MFA for Tier-1; 15-minute kill-switch; offboarding runbook; evidence rights and breach SLAs.

• Regulatory exposure: Open matters/undertakings/fines cataloged; inherited obligations identified.

• Insurance fit: Coverage bound without exclusions that void recovery (e.g., “failure to maintain MFA”); endorsements reflect actual controls.

• Board reporting: Quarterly tabletop with finance/ops/legal; standing dashboard on identity, restore proofs, MTTR, vendor risk, and DR outcomes.

Action Items (to run this week)

1. Pull IdP admin exports and MFA exception logs; close the top five risks within 10 business days.

2. Schedule a crown-jewel timed restore; document RTO/RPO and gaps.

3. Enforce DMARC=reject and disable legacy mail protocols.

4. Tier your top vendors by blast radius; implement SSO/MFA and a 15-minute kill-switch drill.

5. Publish a draft board dashboard with identity health, EDR coverage, MTTR, and restore results.

TL;DR

Cyber diligence is deal math. Your discipline - evidence over narratives, milestones over slogans - preserves the thesis and accelerates value creation. Build the proofs, price the gaps, and run the first 100 days like the integration project it is.

Stay cyber safe—and keep the espresso strong. ☕️