TMA-OCI-2.3

Ensure no network security groups allow ingress from 0.0.0.0/0 to port 22

ÉlevéeNiveau 1Automatiséeoci

Description

Network security groups provide stateful filtering of ingress/egress network traffic to OCI resources. It is recommended that no security group allows unrestricted ingress to port 22. Removing unfettered connectivity to remote console services, such as Secure Shell (SSH), reduces a server's exposure to risk. Flags network security groups with an INGRESS rule from 0.0.0.0/0 covering port 22. Covers every subscribed region and every accessible compartment. Read-only OCI CLI calls; credentials and home region come from the CLI's normal configuration (~/.oci/config, OCI_CLI_PROFILE, OCI_CLI_AUTH). The tenancy OCID is taken from OCI_TENANCY or the first tenancy= line of the config file. A missing CLI or credential fails the check.

Méthode de vérification

Méthode d'audit: Commande shell

shell

t=${OCI_TENANCY:-$(sed -n 's/^[[:space:]]*tenancy[[:space:]]*=[[:space:]]*//p' "${OCI_CLI_CONFIG_FILE:-$HOME/.oci/config}" 2>/dev/null | head -n 1 | tr -d '\r[:space:]')}
[ -n "$t" ] || exit 1
bad=0
cs=$(oci iam compartment list --compartment-id "$t" --compartment-id-in-subtree true --access-level ACCESSIBLE --all --query 'data[?"lifecycle-state"==`"ACTIVE"`].id' --raw-output 2>/dev/null) || exit 1
comps="$t $(printf '%s\n' "$cs" | grep -o 'ocid1\.compartment\.[^"]*')"
rs=$(oci iam region-subscription list --tenancy-id "$t" --query 'data[?status==`"READY"`]."region-name"' --raw-output 2>/dev/null) || exit 1
regions=$(printf '%s\n' "$rs" | grep -o '"[a-z0-9-]*"' | tr -d '"')
[ -n "$regions" ] || exit 1
for r in $regions; do
  for c in $comps; do
    ns=$(oci network nsg list --compartment-id "$c" --region "$r" --all --query 'data[?"lifecycle-state"==`"AVAILABLE"`].id' --raw-output 2>/dev/null) || exit 1
    for g in $(printf '%s\n' "$ns" | grep -o 'ocid1\.networksecuritygroup\.[^"]*'); do
      n=$(oci network nsg rules list --nsg-id "$g" --region "$r" --all --query 'length(data[?direction==`"INGRESS"` && (source==`"0.0.0.0/0"`) && (protocol==`"all"` || (protocol==`"6"` && ("tcp-options"."destination-port-range"==`null` || ("tcp-options"."destination-port-range".min<=`22` && "tcp-options"."destination-port-range".max>=`22`))) || (protocol==`"17"` && ("udp-options"."destination-port-range"==`null` || ("udp-options"."destination-port-range".min<=`22` && "udp-options"."destination-port-range".max>=`22`))))])' --raw-output 2>/dev/null) || exit 1
      [ "${n:-0}" -eq 0 ] || { echo "port 22 open to 0.0.0.0/0: $r $g"; bad=1; }
    done
  done
done
[ "$bad" -eq 0 ] && echo compliant

Sortie attendue: compliant

Méthode de correction

Méthode de correction: Recommandation ou correctif d'infrastructure

Remove or narrow the offending NSG rules (oci network nsg rules remove / update --nsg-id <ocid> ...) so 0.0.0.0/0 cannot reach port 22.

Propriétés

Systèmes d'exploitation: Tous
Étiquettes: ocinetwork
Référence: CIS Oracle Cloud Infrastructure Foundations Benchmark v3.1.1 - 2.3 Ensure no network security groups allow ingress from 0.0.0.0/0 to port 22

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 oci