End-to-end vulnerability management lifecycle — from policy creation and stakeholder buy-in through scanning, prioritization, remediation, and ongoing maintenance using Tenable Nessus on Azure infrastructure.
Simulate a complete vulnerability management program for an organization with zero existing security posture, taking it through policy drafting, stakeholder engagement, authenticated scanning, risk-based prioritization, and programmatic remediation — achieving an 80% reduction in total vulnerabilities across the first remediation cycle.
| Metric | Before | After | Reduction |
|---|---|---|---|
| Total Vulnerabilities | 30 | 6 | 80% |
| Critical | 1 | 0 | 100% |
| High | 10 | 1 | 90% |
| Medium | 19 | 5 | 76% |
- Tenable Nessus — Enterprise vulnerability scanning and assessment
- Azure Virtual Machines — Scan engine and target infrastructure
- PowerShell & Bash — Automated remediation scripting
- Change Advisory Board (CAB) — Governance and approval workflows
- Tenable (enterprise vulnerability management platform)
- Azure Virtual Machines (Nessus scan engine + scan targets)
- PowerShell & BASH (remediation scripts)
- Vulnerability Management Policy Draft Creation
- Mock Meeting: Policy Buy-In (Stakeholders)
- Policy Finalization and Senior Leadership Sign-Off
- Mock Meeting: Initial Scan Permission (Server Team)
- Initial Scan of Server Team Assets
- Vulnerability Assessment and Prioritization
- Distributing Remediations to Remediation Teams
- Mock Meeting: Post-Initial Discovery Scan (Server Team)
- Mock CAB Meeting: Implementing Remediations
- Remediation Round 1: Outdated Wireshark Removal
- Remediation Round 2: Insecure Protocols & Ciphers
- Remediation Round 3: Guest Account Group Membership
- Remediation Round 4: Windows OS Updates
- First Cycle Remediation Effort Summary
This phase focuses on drafting a Vulnerability Management Policy as a starting point for stakeholder engagement. The initial draft outlines scope, responsibilities, and remediation timelines, and may be adjusted based on feedback from relevant departments to ensure practical implementation before final approval by upper management.
Draft Policy
In this phase, a meeting with the server team introduces the draft Vulnerability Management Policy and assesses their capability to meet remediation timelines. Feedback leads to adjustments, like extending the critical remediation window from 48 hours to one week, ensuring collaborative implementation.
YouTube Video: Stakeholder Policy Buy-In Meeting
After gathering feedback from the server team, the policy is revised, addressing aggressive remediation timelines. With final approval from upper management, the policy now guides the program, ensuring compliance and reference for pushback resolution.
Finalized Policy
The team collaborates with the server team to initiate scheduled credential scans. A compromise is reached to scan a single server first, monitoring resource impact, and using just-in-time Active Directory credentials for secure, controlled access.
YouTube Video: Initial Discovery Scan
In this phase, an insecure Windows Server is provisioned to simulate the server team's environment. After creating vulnerabilities, an authenticated scan is performed, and the results are exported for future remediation steps.
We assessed vulnerabilities and established a remediation prioritization strategy based on ease of remediation and impact. The following priorities were set:
- Third Party Software Removal (Wireshark)
- Windows OS Secure Configuration (Protocols & Ciphers)
- Windows OS Secure Configuration (Guest Account Group Membership)
- Windows OS Updates
The server team received remediation scripts and scan reports to address key vulnerabilities. This streamlined their efforts and prepared them for a follow-up review.
The server team reviewed vulnerability scan results, identifying outdated software, insecure accounts, and deprecated protocols. The remediation packages were prepared for submission to the Change Control Board (CAB).
The Change Control Board (CAB) reviewed and approved the plan to remove insecure protocols and cipher suites. The plan included a rollback script and a tiered deployment approach.
The server team used a PowerShell script to remove outdated Wireshark. A follow-up scan confirmed successful remediation.
Wireshark Removal Script
Scan 2 - Third Party Software Removal
The server team used PowerShell scripts to remediate insecure protocols and cipher suites. A follow-up scan verified successful remediation, and the results were saved for reference.
PowerShell: Insecure Protocols & Ciphers Remediation
Scan 3 - Ciphersuites and Protocols
The server team removed the guest account from the administrator group. A new scan confirmed remediation, and the results were exported for comparison.
PowerShell: Guest Account Group Membership Remediation
Scan 4 - Guest Account Group Removal
Windows updates were re-enabled and applied until the system was fully up to date. A final scan verified the changes
The remediation process reduced total vulnerabilities by 80%, from 30 to 6. Critical vulnerabilities were resolved by the second scan (100%), and high vulnerabilities dropped by 90%. Mediums were reduced by 76%. In an actual production environment, asset criticality would further guide future remediation efforts.
After completing the initial remediation cycle, the vulnerability management program transitions into Maintenance Mode. This phase ensures that vulnerabilities continue to be managed proactively, keeping systems secure over time. Regular scans, continuous monitoring, and timely remediation are crucial components of this phase. (See Finalized Policy for scanning and remediation cadence requirements.)
Key activities in Maintenance Mode include:
- Scheduled Vulnerability Scans: Perform regular scans (e.g., weekly or monthly) to detect new vulnerabilities as systems evolve.
- Patch Management: Continuously apply security patches and updates, ensuring no critical vulnerabilities remain unpatched.
- Remediation Follow-ups: Address newly identified vulnerabilities promptly, prioritizing based on risk and impact.
- Policy Review and Updates: Periodically review the Vulnerability Management Policy to ensure it aligns with the latest security best practices and organizational needs.
- Audit and Compliance: Conduct internal audits to ensure compliance with the vulnerability management policy and external regulations.
- Ongoing Communication with Stakeholders: Maintain open communication with teams responsible for remediation, ensuring efficient coordination.
By maintaining an active vulnerability management process, organizations can stay ahead of emerging threats and ensure long-term security resilience.