In every penetration test, certain weaknesses appear repeatedly. Despite new tools, policies, and awareness campaigns, the same foundational misconfigurations continue to provide attackers with their easiest wins.
This report distills findings from hundreds of penetration testing and adversary-emulation engagements across four major industries: Healthcare, Manufacturing, Financial Services, and Legal. It highlights where these organizations are most commonly misconfigured, what those weaknesses mean in business terms, and which fixes deliver the highest return on effort.

Misconfigurations remain one of the most frequent root causes of breaches. They sit in the gray space between technology and process. They are easy to overlook, yet critical to every defense layer. Firewalls, Active Directory structures, and cloud APIs all depend on correct configuration to enforce policy. When those configurations drift or are implemented hastily, they turn into silent entry points.

The objective of this Playbook is not to assign blame, but to bring clarity. By comparing trends across industries, security leaders can benchmark their own environments, focus remediation efforts, and understand which issues are most likely to appear in their next penetration test.

Healthcare

• Common Misconfigurations
  Flat network between clinical and administrative systems
• Business Impact
  Ransomware can move laterally from an email infection to medical devices or EHR servers, posing a potential patient safety risk
• Fix Priority
  CRITICAL
• Recommended Test Type
  Network Pen Test + Adversary Simulation

• Common Misconfigurations
  Default or shared credentials on legacy imaging systems
  Weak or unmonitored backup segmentation
• Business Impact
  Unauthenticated access to patient data; compliance exposure under HIPAA
• Fix Priority
  High
• Recommended Test Type
  Application Pen Test

• Common Misconfigurations
  Outdated third-party integrations (lab vendors, billing APIs)
• Business Impact
  Supply-chain entry vector with poor visibility
• Fix Priority
  Medium
• Recommended Test Type
  External Pen Test

• Common Misconfigurations
  Weak or unmonitored backup segmentation
• Business Impact
  Backups encrypted or destroyed during a ransomware event
• Fix Priority
  High
• Recommended Test Type
  Network Pen Test

Manufacturing

• Common Misconfigurations
  Shared credentials across OT and IT environments
• Business Impact
  Full plant or production-line compromise through single credential theft
• Fix Priority
  CRITICAL
• Recommended Test Type
  Network Pen Test

• Common Misconfigurations
  Lack of monitoring or logging within PLC/SCADA networks
• Business Impact
  Attacker activity is invisible; extended dwell time is possible
• Fix Priority
  High
• Recommended Test Type
  Adversary Emulation

• Common Misconfigurations
  Unpatched engineering workstations and outdated firmware
• Business Impact
  Initial foothold through the exploitation of legacy components
• Fix Priority
  High
• Recommended Test Type
  Network Pen Test

Financial Services

• Common Misconfigurations
  Excessive Active Directory privileges for service accounts
• Business Impact
  Domain compromise enabling access to sensitive financial data
• Fix Priority
  CRITICAL
• Recommended Test Type
  AD Security Essentials Review

• Common Misconfigurations
  MFA is disabled or inconsistently enforced for remote portals
• Business Impact
  Credential stuffing and account takeover risk
• Fix Priority
  High
• Recommended Test Type
  External Pen Test

• Common Misconfigurations
  Unsecured or over-permissive APIs exposing PII
• Business Impact
  Regulatory penalties and erosion of customer trust
• Fix Priority
  High
• Recommended Test Type
  Application Pen Test

Legal

• Common Misconfigurations
  Publicly exposed client or document portals with weak authentication
• Business Impact
  Confidential case data exposed to the public internet
• Fix Priority
  CRITICAL
• Recommended Test Type
  Application Pen Test

• Common Misconfigurations
  Shared client folders with broad internal permissions
• Business Impact
  Unauthorized staff access and potential data leakage
• Fix Priority
  High
• Recommended Test Type
  AD Security Essentials Review

• Common Misconfigurations
  Lack of outbound network filtering
• Business Impact
  Enables data exfiltration and C2 traffic without detection
• Fix Priority
  Medium
• Recommended Test Type
  Network Pen Test

Across industries, three themes emerge:

1. Segmentation Still Fails at the Basics.
   Flat networks, where production, administrative, and vendor systems coexist, remain the most reliable pathway for attackers. When lateral movement is easy, even a low-privilege compromise can escalate rapidly. Segmenting critical systems with strict ACLs and monitoring inter-zone traffic consistently ranks among the most effective risk-reduction measures.
2. Identity and Access Are the New Perimeter.
   Over-permissioned service accounts, weak credential hygiene, and incomplete MFA rollouts consistently top the list of exploitable misconfigurations. Attackers increasingly bypass perimeter defenses entirely by leveraging stolen or inherited credentials that were never properly scoped or rotated.
3. Visibility Gaps Multiply Impact.
   In OT environments, law firms, and cloud-integrated healthcare systems alike, missing telemetry turns minor incidents into major breaches. Without centralized logging, security teams are left piecing together timelines long after the damage is done.

While the technical specifics vary, the business outcomes follow predictable patterns:

• Operational Disruption: Unsegmented networks and shared credentials often translate into ransomware spreading faster than containment can keep up, halting production lines or clinical workflows.
• Regulatory Exposure: Misconfigured APIs, outdated integrations, and uncontrolled data flows trigger compliance investigations and fines.
• Reputational Harm: In sectors built on trust, especially financial and legal, even limited exposure of client or customer information can have long-lasting effects.
• Remediation Costs: Each repeated misconfiguration compounds over time. Fixing them post-incident is exponentially more expensive than addressing them proactively.

Prioritization is essential when resources are limited. Critical items are those that allow privilege escalation, data compromise, or operational shutdown in a single step. High priorities are those that amplify attacker reach or complicate recovery. Medium issues typically require chaining with other weaknesses to become impactful but should still be addressed during planned maintenance cycles.

For most organizations, addressing the top Critical issues in each industry column will eliminate the majority of high-impact exposure points.

Every misconfiguration tells a story, not only of a missed patch or poorly applied control, but of an assumption that went untested. Penetration testing is most valuable when it validates the success of remediation, not merely when it uncovers weaknesses.

Security leaders can use this Playbook as both a diagnostic reference and a planning tool:

1. Benchmark Against Your Industry: Identify which of these findings mirror your own environment. If the issue appears in your industry’s column, odds are high it exists in yours.
2. Prioritize for Impact: Focus on the misconfigurations that directly enable privilege escalation or lateral movement. They have the highest cost if ignored.
3. Verify Remediation: Once controls are implemented, schedule a Verification Pen Test or Adversary Emulation to confirm that those paths are closed. Testing after remediation ensures that the investment in fixes translates to measurable resilience.

Penetration testing is a tool for continuous improvement, a means to prove that controls function as intended under realistic attack conditions.

In our engagements, the organizations that demonstrate the strongest security posture share one common trait: they treat each test as a feedback loop. Findings inform remediation, remediation drives validation, and validation shapes future policy.

Next Steps
Organizations that use this Playbook effectively take three immediate actions:

1. Conduct a Configuration Audit
   Compare current network and identity, and application configurations against the highlighted misconfigurations for your industry.
2. Document Fix Ownership
   Assign clear responsibility for remediation and include validation steps in each change ticket.
3. Plan a Follow-Up Test
   After critical fixes are deployed, run a focused penetration test or emulation exercise to ensure the weaknesses cannot recur.

Attackers depend on predictability. They thrive on the small configuration errors that appear in every environment, regardless of sector or size. Eliminating those predictable pathways is the simplest, most cost-effective way to strengthen your organization’s security posture.