Safeguard 2.7: Allowlist Authorized Scripts

Safeguard 2.7: allowlist authorized scripts requirement is a practical control aimed at a common attacker path: running unauthorized PowerShell, Python, shell scripts, JavaScript, or macro code on endpoints and servers. If your environment lets any user or process execute any script from any location, you have a high-likelihood route for malware, ransomware staging, persistence, and “living off the land” activity. Allowlisting flips the default from “scripts can run unless blocked” to “scripts cannot run unless approved.”

For a Compliance Officer, CCO, or GRC lead, the fastest path is to convert this safeguard into an operating requirement with clear scope, ownership, enforcement, and evidence. You want two outcomes: (1) technical prevention or strong restriction of unapproved script execution, and (2) a repeatable governance workflow that makes exceptions rare, time-bound, and reviewable. This page gives requirement-level implementation guidance you can hand to endpoint engineering, IAM, SecOps, and internal audit without translating it again.

Sources: CIS Controls v8 and the CIS Controls Navigator v8 (CIS Controls v8; CIS Controls Navigator v8).

Regulatory text

Framework requirement (excerpt): “CIS Controls v8 safeguard 2.7 implementation expectation (Allowlist Authorized Scripts).” (CIS Controls v8; CIS Controls Navigator v8)

Operator interpretation: You must implement controls so that only scripts you explicitly authorize can execute, based on defined criteria (publisher, signature, hash, path, or management context). “Allowlist” implies a default-deny posture for script execution or a compensating control set that achieves the same outcome in managed enterprise conditions (CIS Controls v8; CIS Controls Navigator v8).

Plain-English interpretation

• A “script” is any interpreted code that can be executed to perform actions on a system (examples: PowerShell, Bash, Python, JavaScript, VBScript, Windows Script Host, macros, installer scripts).
• “Authorized” means you can point to an owner, an approval record, and a control that enforces the approval decision.
• “Allowlist” means you do not rely on user judgment. The system enforces the rule.

If you cannot technically prevent execution of unknown scripts everywhere, you still need to show an explicit decision: where you enforce allowlisting strictly, where you constrain scripts through other measures (signing, constrained language modes, privileged execution only), and how you monitor and remediate drift.

Who it applies to (entity and operational context)

Entity types: Enterprises, service organizations, and technology organizations implementing CIS Controls v8 (CIS Controls v8; CIS Controls Navigator v8).

Operational scope (what environments auditors expect you to cover):

• Corporate endpoints (Windows, macOS, Linux)
• Servers (on-prem and cloud IaaS)
• VDI and privileged admin workstations
• CI/CD runners and build agents (often overlooked)
• Remote management tooling and automation platforms (RMM, config management, orchestration)

Where allowlisting has the highest risk reduction:

• Administrative scripting environments (PowerShell, shell)
• Places where scripts arrive from email, browsers, chat, or file sync
• Shared admin jump boxes and “tooling servers” used by multiple teams

What you actually need to do (step-by-step)

Step 1: Define “script” and “authorized” in a control card

Create a short requirement control card that engineering and auditors can both use:

• Objective: Only approved scripts execute; unapproved scripts are blocked or prevented from running in controlled zones.
• Owner: Endpoint/security engineering with GRC oversight.
• In-scope assets: Endpoints, servers, admin workstations, CI/CD runners (list categories).
• Enforcement standard: What attributes qualify a script as authorized (signing certificate, trusted publisher, hash, managed path).
• Exceptions: Break-glass rules, time limits, compensating monitoring, and who approves (CIS Controls v8).

This is the fastest way to eliminate “we thought someone else owned it.”

Step 2: Establish script trust criteria (what gets onto the allowlist)

Pick criteria that you can maintain at scale:

• Preferred: Signed scripts from approved signing certs, with certificate lifecycle ownership.
• Acceptable for narrow cases: Hash allowlisting for a small set of stable scripts.
• Use with caution: Path-based rules, because attackers often find writeable paths.

Document the criteria and align it to execution tools your teams already run (admin automation, IT scripts, developer tooling). If your teams cannot sign scripts yet, treat that as an implementation gap and make signing the near-term target state.

Step 3: Implement technical enforcement (default deny where it matters)

Your technical pattern should answer one question: What happens when an unapproved script is executed?

• Block/Prevent in high-risk zones: privileged workstations, server admin contexts, sensitive production servers.
• Restrict in general user zones: allow only signed scripts or only scripts executed by managed tooling.
• Detect + Respond only as a temporary state, with explicit timeline to enforce blocking.

Common enterprise mechanisms include application control and script control capabilities provided by endpoint platforms and OS features. The audit standard is not the brand; it’s the demonstrable prevention of unauthorized script execution plus proof of ongoing operation.

Step 4: Build the authorization workflow (request → review → approve → deploy)

Implement a lightweight, auditable workflow:

1. Request intake: Ticket with script name, purpose, owner, target systems, execution method, source repo, and requested duration.
2. Security review: Confirm least privilege, no embedded secrets, logging behavior, and safe execution context.
3. Approval: Named approver and date; map approval to the trust mechanism (signing cert, publisher, hash rule).
4. Deployment: Controlled rollout via endpoint management or policy distribution.
5. Validation: Test evidence that the script runs when authorized and fails when not.

Keep the workflow strict for production and privileged contexts. For developer workstations, you can allow more flexibility, but you still need defined controls and boundaries.

Step 5: Manage exceptions as time-bound risk decisions

You will need exceptions (incident response scripts, vendor-provided scripts, emergency patch actions). Make exceptions:

• Time-bound with an expiration date
• Scoped to specific hosts or groups
• Logged with a reason and approving authority
• Reviewed on a schedule, with closure evidence

Auditors focus on whether exceptions are controlled or whether they quietly become the real policy.

Step 6: Run control health checks and remediate drift

Operationalize routine checks:

• Policy drift: Machines not receiving policies, agents unhealthy, enforcement set to audit-only.
• Execution attempts: Alerts on blocked scripts, new script interpreters, or suspicious script hosts.
• Allowlist hygiene: Stale entries, expired certs, orphaned script owners.

Track findings to closure with tickets, owners, and dates (CIS Controls v8).

Required evidence and artifacts to retain

Auditors and customers typically want evidence that is both designed and operating. Maintain an “evidence bundle” per review cycle (CIS Controls v8):

Governance artifacts

• Control card (objective, scope, owner, cadence, exceptions)
• Script allowlisting standard (what qualifies as authorized)
• Exception standard (who can approve, duration, compensating controls)

Operational artifacts

• Current allowlist export or policy configuration snapshot
• Sample approvals (tickets) mapped to allowlist entries
• Evidence of enforcement mode (e.g., policy setting screenshots/exports)
• Logs or reports showing blocked/allowed events, plus triage notes
• Control health check report and remediation tracker

Retention and accessibility

Store evidence in a GRC repository or controlled folder structure with consistent naming. If you use Daydream to manage requirement control cards and evidence bundles, keep links to the underlying system exports so an auditor can validate integrity without reverse-engineering your environment.

Common exam/audit questions and hangups

Expect these questions, and pre-answer them in your control card and evidence bundle:

• “Define script.” If you only mention PowerShell, you will miss Python, shell, and macro paths.
• “Show me enforcement.” Auditors ask for proof that unapproved scripts fail to execute in scope.
• “How do you approve scripts?” They look for a workflow, not an email thread.
• “What about administrators?” Admin script execution is the high-risk case; carve-outs need strong justification.
• “How do you review exceptions?” “We do it ad hoc” reads as “we don’t.”

Frequent implementation mistakes and how to avoid them

1. Policy-only allowlisting. Fix: require a technical control that blocks or restricts execution and show logs.
2. Allowlisting by path in user-writable directories. Fix: prefer signing or publisher rules; lock down write permissions if path rules are unavoidable.
3. No owner for the signing certificate. Fix: treat code signing like identity infrastructure with lifecycle management.
4. Audit-only mode forever. Fix: define an enforcement ramp with explicit milestones, plus compensating controls during transition.
5. Exceptions with no expiry. Fix: default to expiration and require renewal approval.

Enforcement context and risk implications

No public enforcement cases were provided in the supplied source catalog for this safeguard, so this page does not cite specific regulator actions.

Operationally, script allowlisting reduces the likelihood that common malware delivery and post-exploitation techniques succeed. If you fail this control, your risk profile usually shows up as:

• Higher incident response frequency tied to script-based tooling
• Broader blast radius from phishing and credential theft
• Audit findings framed as “insufficient control over code execution” rather than a narrow configuration gap

Practical 30/60/90-day execution plan

Use phases rather than calendar promises. Your actual speed depends on endpoint tooling, asset sprawl, and engineering capacity.

First 30 days (Immediate foundation)

• Publish the control card: scope, owner, enforcement intent, and exception rules (CIS Controls v8).
• Define script categories in scope (PowerShell, shell, Python, macro, etc.).
• Identify highest-risk zones (privileged workstations, production servers, CI/CD runners).
• Stand up the request/approval workflow and evidence bundle format (CIS Controls v8).
• Establish a baseline report: where scripts currently execute and from where.

Days 31–60 (Enforcement in critical zones)

• Implement blocking or strict restriction in privileged/admin zones first.
• Roll out signing or publisher-based authorization for core admin scripts.
• Train IT and SecOps on the intake workflow and what “authorized” means.
• Start exception handling with expirations and a review cadence.
• Run the first control health check and open remediation tickets (CIS Controls v8).

Days 61–90 (Scale and stabilize)

• Expand enforcement to broader endpoint populations, with defined tiers if needed.
• Reduce path- and hash-based allowlisting; migrate toward signed scripts.
• Add monitoring for repeated blocks and anomalous script interpreters.
• Produce an audit-ready packet: policy exports, sample approvals, health check results, and exception register.

Ongoing, keep the allowlist clean, keep the workflow fast, and keep evidence packaged. Daydream fits well here as the system of record for control cards, recurring health checks, and evidence bundles tied to each operating cycle.

Frequently Asked Questions

What counts as a “script” for Safeguard 2.7?

Treat any interpreted or automation code as a script, including PowerShell, Bash/shell, Python, JavaScript/VBScript, and macro-style code. Define your in-scope script types explicitly in the control card so engineering and auditors apply the same boundary (CIS Controls v8).

Do we need full default-deny across every workstation on day one?

No, but you do need a documented scope and a credible enforcement plan that prioritizes high-risk zones. Auditors usually accept phased rollout when strict controls exist for privileged and production contexts and you can show progress with evidence (CIS Controls v8).

Is monitoring enough, or must we technically block unapproved scripts?

Allowlisting implies prevention or strong restriction, not only detection, because the safeguard is about controlling execution. If you start with audit-only monitoring, document it as a temporary state with compensating controls and a defined move to enforcement (CIS Controls v8; CIS Controls Navigator v8).

How do we handle third-party scripts from vendors or consultants?

Require the same intake and approval workflow, plus a clear owner for the script’s purpose and lifecycle. Prefer vendor-signed scripts or re-sign internally after review, and scope exceptions tightly if you cannot meet the trust standard immediately.

What evidence is most persuasive in an audit?

A policy export showing the allowlist rules, a small set of approvals mapped to specific allowlist entries, and logs showing blocked execution attempts in scope. Pair that with a control health check report and tracked remediation to show ongoing operation (CIS Controls v8).

Who should own Safeguard 2.7: allowlist authorized scripts requirement?

Endpoint/security engineering typically owns technical enforcement, with SecOps owning monitoring and triage. GRC should own the control card, evidence expectations, and review cadence so the requirement survives tool changes and org churn (CIS Controls v8).