Insecure Services Documentation

PCI DSS 4.0.1 Requirement 2.2.5 requires you to document every insecure service, protocol, or daemon that still exists in your environment, why the business must keep it, and what compensating security features you implemented to reduce the risk. To operationalize it, build an “insecure services register” tied to asset inventory, approvals, and technical controls, then retain evidence that the mitigations are deployed and working. (PCI DSS v4.0.1 Requirement 2.2.5)

Key takeaways:

• Maintain a current inventory of insecure services/protocols/daemons that are present, even if “temporarily” or “legacy.”
• For each one, keep written business justification plus documented, implemented risk-reducing security features. (PCI DSS v4.0.1 Requirement 2.2.5)
• Auditors look for traceability: discovery → approval → mitigation → validation → periodic review, with artifacts at each step.

“Insecure services documentation requirement” is not a paperwork exercise; it is a control that forces governance over exceptions. PCI DSS expects you to disable insecure services, protocols, and daemons where possible, and where you cannot, to prove you understand the risk and have reduced it with concrete security measures. Requirement 2.2.5 is the part that becomes painful during an assessment because it sits at the intersection of infrastructure reality (what’s actually running), change management (who approved it), and defensive engineering (what protects it). (PCI DSS v4.0.1 Requirement 2.2.5)

For a Compliance Officer, CCO, or GRC lead, the fastest path is to treat this as a register-and-evidence workflow: discover insecure services in scope, document why they exist, require formal approval, define a minimum mitigation pattern, validate the mitigations, and re-check on a recurring basis. Your goal is that any assessor can pick one insecure protocol (for example, Telnet, FTP, older TLS configurations, or SNMPv1/v2c), and you can immediately produce a complete packet: justification, controls, implementation proof, and ownership. (PCI DSS v4.0.1 Requirement 2.2.5)

Regulatory text

Requirement statement: “If any insecure services, protocols, or daemons are present, business justification is documented, and additional security features are documented and implemented that reduce the risk of using insecure services, protocols, or daemons.” (PCI DSS v4.0.1 Requirement 2.2.5)

Operator meaning: If an insecure service or protocol exists anywhere in the PCI DSS scope (and often in connected environments that could impact the CDE), you need two things per instance:

1. written business justification for keeping it, and
2. written and implemented security features that reduce the risk.
   Documentation alone fails if you cannot prove the mitigations are actually deployed and operating. (PCI DSS v4.0.1 Requirement 2.2.5)

Plain-English interpretation

You must know where insecure services/protocols are running, and you must manage them as approved exceptions with compensating controls. If you cannot justify a service, it should not be present. If you can justify it, you must harden the surrounding environment so the insecure element cannot be easily abused. (PCI DSS v4.0.1 Requirement 2.2.5)

“Insecure” is context-dependent, but common examples include cleartext management protocols, legacy cryptography, and services that lack strong authentication or encryption by design. Your process should not rely on a static list; it should rely on discovery plus risk review.

Who it applies to (entity and operational context)

Entity types: Merchants, service providers, and payment processors with PCI DSS scope. (PCI DSS v4.0.1 Requirement 2.2.5)

Operational context where it shows up:

• CDE and supporting networks: servers, network devices, security tools, hypervisors, container hosts, and administrative jump paths.
• Third-party managed infrastructure: hosted POS, managed firewalls, outsourced sysadmin, cloud-managed appliances. You still need the documentation and evidence, even if a third party operates the system day to day.
• Legacy dependencies: old middleware, embedded devices, or vendor-managed appliances where the manufacturer requires an older protocol for support.

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

1) Define “insecure services/protocols/daemons” for your environment

Create a short internal standard that states:

• insecure services/protocols are those that are unencrypted, weakly authenticated, obsolete, or not aligned to your approved secure configuration baseline
• the system owner must either remove/disable them or open an exception under Requirement 2.2.5 (PCI DSS v4.0.1 Requirement 2.2.5)

Keep this definition practical. The goal is consistent decisions and repeatable evidence.

2) Perform discovery and build an “Insecure Services Register”

Build a register (spreadsheet, GRC record, or CMDB-backed list) that captures, at minimum:

• Asset identifier (hostname, IP, device ID, cloud resource ID)
• Environment and scope tag (CDE, connected-to-CDE, corporate)
• Service/protocol/daemon name and port
• Purpose and dependency (what breaks if removed)
• Owner (person/team accountable)
• Status: remove, mitigate, or exception requested

Populate it from:

• configuration management outputs
• vulnerability scanning results
• port/service discovery
• firewall rule reviews
• engineering attestations for systems scanners cannot reach

3) Force a decision: remove, replace, or formally justify

For each register entry, require one of three outcomes:

• Remove/disable (preferred)
• Replace/upgrade to a secure alternative
• Keep under exception with documented justification and mitigations (PCI DSS v4.0.1 Requirement 2.2.5)

Your intake form for exceptions should prohibit vague rationales like “legacy” without a dependency and a plan.

4) Document business justification (what auditors expect to see)

Your justification should read like an approval memo, not a ticket comment. Include:

• why the insecure element is needed (vendor support requirement, device limitation, interoperability)
• why secure alternatives are not currently feasible (technical constraint, contractual limitation)
• scope boundaries (where it exists and where it must not exist)
• owner accountability and review cadence (review triggers: system upgrade, vendor change, architecture change)

This satisfies the “business justification is documented” clause. (PCI DSS v4.0.1 Requirement 2.2.5)

5) Specify “additional security features” as a standard mitigation pattern

Create a minimum mitigation checklist that you can apply consistently. Examples (pick what fits your architecture):

• network segmentation or strict ACLs so only required sources can reach the service
• jump hosts / bastion access and removal of direct admin access paths
• MFA on the access path that leads to the insecure protocol (where applicable)
• IP allowlisting plus time-bound access windows
• enhanced monitoring: logs collected, alerts tuned to misuse patterns
• configuration hardening on the service/daemon (disable anonymous access, restrict commands, bind to management interface only)
• compensating encryption wrapper (for example, tunneling), if appropriate to your environment

Then, for each insecure service entry, document exactly which features are in place and where they are configured. This satisfies “additional security features are documented and implemented.” (PCI DSS v4.0.1 Requirement 2.2.5)

6) Prove implementation (not intent)

For each mitigation, define the evidence type in advance:

• firewall/ACL rule export showing restricted source/destination
• system configuration excerpts showing service binding and settings
• change records approving the mitigations
• screenshots or CLI outputs (dated) showing controls enabled
• SIEM log source onboarding proof and sample alert evidence

Store evidence alongside the register entry so it can be produced on demand.

7) Add change-management gates so new insecure services cannot “sneak in”

Insert two gates into your operational workflows:

• Build/deploy gate: secure baseline checks that fail builds when prohibited services are enabled
• Change gate: any request enabling a risky protocol requires security review and 2.2.5 documentation before implementation

8) Review and refresh continuously

Treat the register as living operational documentation:

• update entries after patching, migrations, vendor swaps, or network redesign
• close exceptions when the insecure element is removed
• revalidate mitigations when firewall rules or monitoring stacks change

Required evidence and artifacts to retain

Keep a tidy packet per insecure service/protocol/daemon:

Core documentation

• Insecure Services Register (current)
• Exception request with business justification and approvals (PCI DSS v4.0.1 Requirement 2.2.5)
• Risk acceptance sign-off (who accepted, what scope, what conditions)

Technical evidence

• Discovery evidence (scan output, port inventory report, config output)
• Mitigation implementation proof (ACLs, configs, MFA enforcement, jump host design)
• Monitoring evidence (log source enabled, alert rules, sample events)

Operational evidence

• Change tickets that implemented mitigations
• Validation record (who checked, what was checked, date, result)
• Periodic review notes and closure records when removed

Tooling note: Many teams use Daydream to centralize these exception records and evidence attachments so the register, approvals, and screenshots do not fragment across tickets, wikis, and shared drives.

Common exam/audit questions and hangups

Assessors and internal audit often probe these angles:

• “Show me every insecure service present in scope and how you know the list is complete.”
• “Pick one entry. Where is the business justification documented?” (PCI DSS v4.0.1 Requirement 2.2.5)
• “Show me the additional security features, and show me proof they are implemented.” (PCI DSS v4.0.1 Requirement 2.2.5)
• “Who approved the exception, and what would trigger removal?”
• “How do you prevent reintroduction after a rebuild or vendor maintenance?”

Hangups that stall audits:

• no single owner for each exception
• mitigations described generically (“restricted by firewall”) with no rule evidence
• discovery is ad hoc, so the inventory cannot be defended

Frequent implementation mistakes and how to avoid them

1. Documenting justification but not controls. Fix: require a mitigation checklist and attach the exact config/rule evidence. (PCI DSS v4.0.1 Requirement 2.2.5)
2. Controls exist but are not tied to the exception record. Fix: link change tickets, firewall objects, and monitoring alerts directly in the register.
3. Over-scoping the exception. Fix: state exact hosts, ports, and allowed source ranges; reject “needed across the network.”
4. No exit plan. Fix: add a removal trigger (upgrade date, vendor EOL, architecture milestone) and track it.
5. Treating third-party systems as “not our problem.” Fix: contractually require the third party to provide the same documentation and evidence packet; keep it in your repository.

Enforcement context and risk implications

No public enforcement cases were provided in the supplied sources. Practically, this control maps to common breach paths: attackers search for legacy protocols, weak management services, and cleartext access routes. Requirement 2.2.5 is how you demonstrate you intentionally constrained those paths and can prove it under assessment. (PCI DSS v4.0.1 Requirement 2.2.5)

A practical 30/60/90-day execution plan

First 30 days (stabilize and create the register)

• Assign an owner for the insecure services documentation program (usually Security Engineering with GRC governance).
• Publish the exception template: business justification + required mitigation categories + approval workflow. (PCI DSS v4.0.1 Requirement 2.2.5)
• Run initial discovery and stand up the Insecure Services Register with owners and scope tags.
• Triage: label entries as remove/replace/exception-needed.

Days 31–60 (close gaps and produce defensible evidence)

• For each exception-needed entry, collect written justification and route approvals.
• Implement standard mitigations (segmentation/ACL, access path control, monitoring) and capture evidence artifacts. (PCI DSS v4.0.1 Requirement 2.2.5)
• Add change-management gates so new insecure services require review before enablement.

Days 61–90 (operationalize and make it audit-ready)

• Perform a second discovery pass to confirm the register matches reality.
• Validate mitigations with spot checks and document validation results.
• Hold an exception review meeting with system owners and set removal triggers.
• Centralize evidence storage (for example in Daydream) so each register record has a complete assessor-ready packet.

Frequently Asked Questions

What counts as an “insecure service, protocol, or daemon” under PCI DSS 2.2.5?

PCI DSS 2.2.5 does not provide a single fixed list in the provided excerpt; treat “insecure” as services/protocols that are cleartext, weakly authenticated, obsolete, or inconsistent with your secure configuration baseline. What matters is that if one is present, you document justification and mitigations, and you can prove implementation. (PCI DSS v4.0.1 Requirement 2.2.5)

If an insecure protocol is enabled but “not used,” do we still need documentation?

Yes. The requirement triggers on presence. If it is enabled and reachable, treat it as present, then remove it or document justification and risk-reducing security features. (PCI DSS v4.0.1 Requirement 2.2.5)

Can we satisfy 2.2.5 with a policy statement that “we don’t use insecure protocols”?

No. You need system-level evidence. Auditors expect an inventory of what is present plus a per-item justification and implemented mitigations where exceptions exist. (PCI DSS v4.0.1 Requirement 2.2.5)

Who should approve the business justification?

Use an accountable business owner for the system or service, with security review and explicit acceptance of the residual risk. The approval must be recorded and tied to the specific asset and protocol. (PCI DSS v4.0.1 Requirement 2.2.5)

What are “additional security features” in practice?

They are compensating measures that reduce exploitability, such as tight network restrictions, controlled admin paths, and stronger monitoring around the insecure protocol. Your documentation must match what is actually configured. (PCI DSS v4.0.1 Requirement 2.2.5)

How do we handle insecure services running on third-party managed systems?

Treat the third party as a dependency, not an exemption. Require the third party to provide the same justification and mitigation evidence and store it with your 2.2.5 records so you can produce it during assessment. (PCI DSS v4.0.1 Requirement 2.2.5)