IT Asset Management (ITAM) und Cybersicherheit: Alles inventarisieren, alles schützen

“You can’t protect what you don’t know you have.”—this principle is the foundation of every security strategy. IT Asset Management (ITAM) ensures that companies maintain a complete, up-to-date overview of all IT assets: hardware, software, cloud resources, licenses, and their dependencies.

Why ITAM Is the Foundation of Every Security Strategy

The unpatched asset problem:

Scenario: Ransomware attack in October 2024
  Entry point: CVE-2024-XXXX in Windows Server 2012 R2
  Question: "Do we still have Windows 2012 R2 systems?"
  Answer without ITAM: "We don't think so..."
  Reality: 3 forgotten VMs in the basement ESXi

Why does this happen?
  → Organic IT growth over the years
  → No structured handover during staff turnover
  → Shadow IT: Departments make purchases without the IT department
  → Cloud sprawl: Teams create EC2 instances, then forget about them
  → Virtualization: VMs are cloned, renamed, and forgotten

CIS Controls 1 and 2 require exactly that:
  Control 1: Inventory and control of enterprise assets
  Control 2: Inventory and control of software assets

ITAM gaps = security gaps:
  Unknown asset → no patch → known CVE → attack

Statistics:
  → 20% of IT assets in medium-sized companies are not inventoried
    (Freshservice State of IT, 2023)
  → 67% of ransomware attacks exploit unpatched known CVEs
    (IBM X-Force, 2024)

CMDB - Configuration Management Database

CMDB Concept (according to ITIL):

Configuration Item (CI):
  → Any asset that is managed
  → Has attributes: Name, Type, Version, Owner, Location, Status
  → Types: Hardware, Software, Service, Document, Certificate

CMDB Structure Example:

CI: web-prod-01
  Type:        Physical Server
  Model:      Dell PowerEdge R750
  OS:         Ubuntu 22.04 LTS
  IP:         10.0.2.10
  MAC:        00:50:56:AB:CD:EF
  Rack:       Data Center DC1, Rack-03, U 12-14
  Owner: IT Operations
  Application: Nginx 1.24, Node.js 20.x, PostgreSQL 15
  Last Patch: 2026-02-28
  Next Patch: 2026-03-28
  End-of-Life: 2027-06-30 (Hardware)
  Dependencies: → load-balancer-01, → db-cluster-01

Relationships in the CMDB:
  web-prod-01 → uses → nginx:1.24 (Software)
  web-prod-01 → connected-to → db-cluster-01 (Server)
  web-prod-01 → hosted-on → esxi-host-02 (if VM)
  nginx:1.24  → has-vulnerability → CVE-2023-44487 (HTTP/2 Rapid Reset)

CMDB Tools:
  Open Source:
    → iTop (CMDB + ITSM, free)
    → Ralph (excellent open-source ITAM tool)
    → NetBox (network/data center-focused)
    → Snipe-IT (asset tracking, very user-friendly)

  Commercial:
    → ServiceNow CMDB (enterprise standard)
    → Freshservice CMDB (SME/mid-market)
    → Lansweeper (very good for automatic discovery)
    → Device42 (CMDB + Discovery + Dependency Mapping)

Automatic Asset Discovery

How to find assets you don’t know about:

Network scan-based discovery:

Nmap for basic inventory:
# Discover all active hosts on the network
nmap -sn 10.0.0.0/16 -oX discovery.xml

# Identify operating system and services
nmap -O -sV 10.0.0.0/16 -oX inventory.xml

# Only specific ports (faster for large networks)
nmap -p 22,80,443,3389,445 10.0.0.0/16 --open

# Output to CSV for Excel/import
nmap -p 22,80,443 10.0.0.0/16 -oG - | \
  awk '/Up/{print $2}' > live-hosts.txt

Nessus Essentials (free for up to 16 IPs):
  → Combined vulnerability scan + asset discovery
  → Identifies OS, patches, services, configuration issues
  → Export as CSV/XML for CMDB import

OpenVAS (free, unlimited):
  → Comprehensive vulnerability scanner
  → Asset discovery as a byproduct
  → Regular updates to the vulnerability database

Agent-based discovery:
  → Lansweeper Agent: installed on endpoints
  → Regularly sends complete hardware/software inventory
  → Also finds assets behind NAT / in remote offices

Cloud asset discovery:
  AWS:
    aws ec2 describe-instances --query \
      'Reservations[].Instances[].[InstanceId,State.Name,
       PublicIpAddress,PrivateIpAddress,Tags[?Key==`Name`].Value|[0]]' \
      --output table

  Azure:
    az resource list --output table

  GCP:
    gcloud compute instances list

  Multi-Cloud:
    → Prisma Cloud: all clouds in a single overview
    → Wiz: Cloud Asset Inventory + Risk Assessment
    → Combine AWS Security Hub + Azure Security Center

Software Asset Management and SBOM

Software Inventory - why it's so important:

Software inventory minimum requirements:
  → Name and version of every installed application
  → License information (compliance!)
  → Patch status and known CVEs
  → Installed for whom? (Asset association)
  → Installation date and last update

Automatic software inventory:

Windows (WMI):
wmic product get Name, Version, InstallDate, InstallLocation

# Via PowerShell (all installed programs):
Get-WmiObject -Class Win32_Product | Select Name,Version,Vendor |
  Sort Name | Export-Csv software-inventory.csv

# Better: Also from the registry:
Get-ChildItem HKLM:\Software\Microsoft\Windows\CurrentVersion\Uninstall |
  Get-ItemProperty | Select DisplayName,DisplayVersion,Publisher |
  Sort DisplayName

Linux (Debian/Ubuntu):
dpkg --list | awk '{print $2, $3}' > software-inventory.txt

# RPM (RHEL/CentOS):
rpm -qa --queryformat '%{NAME} %{VERSION}\n' > software-inventory.txt

SBOM (Software Bill of Materials):

What is SBOM?
  → Complete inventory of all software components
  → Includes all libraries and their dependencies
  → Standard formats: SPDX (ISO/IEC 5962), CycloneDX
  → Mandatory under a U.S. Executive Order (May 2021) for U.S. government software
  → Increasingly expected in the EU under NIS2 and the CRA (Cyber Resilience Act)

Generate an SBOM with Syft:
# Scan a Docker image:
syft myapp:latest -o spdx-json > sbom-myapp.json

# Scan a source code repository:
syft dir:./src -o cyclonedx-json > sbom-source.json

# Check SBOM for vulnerabilities with Grype:
grype sbom:./sbom-myapp.json

# Shows: all known CVEs in dependencies!

Log4Shell lesson: "Am I using log4j?"
  Without SBOM: weeks of manual searching
  With SBOM: grep "log4j" sbom-*.json → immediate answer

Hardware Lifecycle Management

Hardware Lifecycle and Security Risks:

End-of-Life (EOL) / End-of-Support (EOS):

  EOL means: no more security patches!
  Every known vulnerability remains permanently unpatched.

Critical EOL dates (2026):
  Windows 10:          October 2025 (EOS!) → migrate immediately!
  Windows Server 2012: October 2023 (EOS!) → migrate immediately!
  Windows Server 2016: January 2027 → Plan migration!
  PHP 8.1:             December 2025 → Upgrade!
  CentOS 7:            June 2024 (EOS!) → Migrate!
  Python 3.8:          October 2024 (EOS!)

ITAM Process for EOL Management:
  1. Record all assets with OS/software version in CMDB
  2. Automatically load EOL data from vendor feeds
  3. Trigger alert when < 12 months until EOL
  4. Budget planning: Allocate budget for migration/replacement
  5. Document exceptions + accept risk + mitigate

Hardware replacement cycle:
  Workstations:    4–5 years
  Laptops:         3–4 years
  Servers:          5–7 years
  Network switches: 7–10 years (with firmware support!)
  Firewalls:       3–5 years
  Storage:         5–7 years

Why short cycles? Hardware security vulnerabilities:
  → Spectre/Meltdown: Hardware firmware update required
  → Log4Shell on embedded devices: rarely patchable
  → Older hardware: no TPM 2.0 → no Windows 11, no BitLocker
  → IoT devices: often no security updates after 2–3 years

ITAM for Compliance

ITAM requirements in standards and laws:

ISO 27001:2022:
  A.5.9: Inventory of information and other assets
    → "Complete and up-to-date inventory"
    → Classification based on protection requirements

  A.5.10: Acceptable use of information and other assets
    → Usage rules for classified assets

  A.5.11: Return of assets
    → Exit procedure: return all assets!

NIS2 Art. 21:
  → "Assets and risks must be known"
  → Complete asset inventory as a basis

BSI IT-Grundschutz:
  ORP.1: Organization
  → Asset inventory explicitly required

Audit documentation:
  What auditors want to see:
  □ Complete asset inventory (< 6 months old)
  □ Asset owners for all critical assets
  □ Classification by protection requirements
  □ EOL/EOS management documented
  □ Process for new assets (onboarding) and old ones (decommissioning)
  □ Regular review (frequency documented)

Quick-win checklist:
  □ Create inventory table (asset, owner, OS, version, IP)
  □ Nmap scan against your own network: what unknowns are found?
  □ Windows WSUS / SCCM: how many devices are missing patches?
  □ Identify all devices that haven’t been updated in > 90 days
  □ EOL check: which OS/software is running out of support?