Virtual machines must remove unnecessary serial port devices

MoyenneNiveau 1Automatiséevmware

Description

Removing unnecessary devices from virtual machines minimizes the attack surface and reduces potential pathways for data exfiltration or unauthorized data capture. This practice aligns with the principle of least functionality, ensuring that VMs have only the essential components required to perform their designated functions. Expected: serialN.present absent or "FALSE". The audit parses every .vmx file under /vmfs/volumes/ on the host and lists the VMs that do not comply; it passes when none are found (or no VMs exist). Runs in the ESXi Shell (busybox sh) as root.

Méthode de vérification

Méthode d'audit: Commande shell

shell

command -v find >/dev/null 2>&1 || exit 1
out=$(find /vmfs/volumes/ -maxdepth 3 -type f -name '*.vmx' 2>/dev/null | while IFS= read -r f; do
  awk -v KEYRE='^serial[0-9]+[.]present$' -v MODE='not' -v VAL='TRUE' 'BEGIN { re = tolower(KEYRE) }
{ line = $0; sub(/^[ \t]+/, "", line); i = index(line, "="); if (i == 0) next
  k = tolower(substr(line, 1, i - 1)); sub(/[ \t]+$/, "", k)
  v = substr(line, i + 1); sub(/^[ \t]*"?/, "", v); sub(/"?[ \t\r]*$/, "", v); v = tolower(v)
  if (k ~ re) { seen = 1; if (MODE == "not" && v == tolower(VAL)) bad = bad " " k "=" v
                else if (MODE != "not" && MODE != "ge" && v != tolower(VAL)) bad = bad " " k "=" v
                else if (MODE == "ge" && (v + 0) < (VAL + 0)) bad = bad " " k "=" v } }
END { if ((MODE == "eq" || MODE == "ge") && !seen) bad = " " KEYRE " not set"
      if (bad != "") print FILENAME ":" bad }' "$f"
done)
[ -z "$out" ] && echo compliant || printf '%s\n' "$out" | head -n 25

Sortie attendue: compliant

Méthode de correction

Méthode de correction: Recommandation ou correctif d'infrastructure

To disconnect all serial ports from VMs, run the following PowerCLI command: # In this Example you will need to add the functions from this post: http://blogs.vmware.com/vipowershell/2012/05/working-with-vm-devices-in- powercli.html # Remove all Serial Ports attached to VMs Get-VM | Get-SerialPort | Remove-SerialPort The VM will need to be powered off for this change to take effect.

Propriétés

Systèmes d'exploitation: Tous
Étiquettes: vmwareesxivirtual-machine
Référence: CIS VMware ESXi 9.0 Benchmark v1.0.0 - 7.13 Virtual machines must remove unnecessary serial port devices

Vérifier cet hôte

Exécutez cette commande sur une machine que vous êtes autorisé à auditer. L'analyse est en lecture seule.

shell

tmaegis scan --target vmware