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

高等級 1自動化oci

說明

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.

檢查方式

稽核方法: Shell 指令

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

預期輸出: compliant

修補方式

修補方法: 操作指南或基礎設施修補檔

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.

屬性

作業系統: 不限
標籤: ocinetwork
參考資料: 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

檢查此主機

請在您有權稽核的機器上執行此指令。掃描為唯讀操作。

shell

tmaegis scan --target oci