Port Leak Checker — Scan scripts

These scripts run on the device under test and probe this server across the Nmap top ~130 TCP ports. Enter the Port Leak Checker host (its IP, or portleak.link) as the target. The PowerShell script accepts multiple targets — add more lines to the $targets list; the bash and sh scripts take one target per run.

Because this server never replies, the scripts may print little or nothing even when a port is open end-to-end. The authoritative result is the capture log: run a script, then filter the log by the test device's source IP to see exactly which probes arrived.

Windows PowerShell — Nmap top ~130 TCP ports

Enter the Port Leak Checker host in $targets. Add more lines to scan multiple targets. Prints each open port as it connects. Paste into a PowerShell window, or save as scan.ps1 and run it.

$targets = @(
    "portleak.link"        # <- the Port Leak Checker host (IP or hostname)
    # "203.0.113.10"       # add more targets here if needed
)

$ports = @(80,23,443,21,22,25,3389,110,445,139,143,53,135,3306,8080,1723,111,995,993,5900,1025,587,8888,199,1720,465,548,113,81,6001,10000,514,5060,179,1026,2000,8443,8000,32768,554,26,1433,49152,2001,515,8008,49154,1027,5666,646,5000,5631,631,49153,8081,2049,88,79,5800,106,2121,1110,49155,6000,513,990,5357,427,49156,543,544,5101,144,7,389,8009,3128,444,9999,5009,7070,5190,3000,5432,3986,13,1029,9,6646,49157,1028,873,1755,2717,4899,9100,119,37,1000,3001,5001,82,10010,1030,9090,2107,1024,2103,6004,1801,19,8031,1041,255,3703,17,808,3689,1031,1071,5901,9102,9000,2105,636,1038,2601,7000,5985)

foreach ($ip in $targets) {
    $ports | ForEach-Object {
        $test = New-Object System.Net.Sockets.TcpClient
        $wait = $test.BeginConnect($ip, $_, $null, $null)
        if ($wait.AsyncWaitHandle.WaitOne(250, $false) -and $test.Connected) {
            Write-Output "$ip`:$_ open"
        }
        $test.Close()
    }
}

Linux bash — /dev/tcp port scan

Uses bash's built-in /dev/tcp, so no extra tools are needed. Pass the Port Leak Checker host as the first argument. One target per run.

#!/bin/bash
# Usage: ./portscan.sh <ip-or-hostname> [start-port] [end-port]
# e.g.   ./portscan.sh portleak.link 1 1024
if [ -z "$1" ]; then
    echo "Usage: portscan.sh <ip-or-hostname> [start-port] [end-port]"
    echo "start-port defaults to 1, end-port defaults to 1024"
    exit 1
fi
TARGET="$1"
START_PORT="${2:-1}"
END_PORT="${3:-1024}"
echo "Scanning $TARGET (ports $START_PORT to $END_PORT)"
echo "PORT      STATE  SERVICE"
for PORT in $(seq "$START_PORT" "$END_PORT"); do
    if (echo > "/dev/tcp/$TARGET/$PORT") 2>/dev/null; then
        SERVICE=$(grep -w "${PORT}/tcp" /etc/services | head -n1 | awk '{print $1}')
        echo "$PORT/tcp open  $SERVICE"
    fi
done

POSIX sh — curl port loop

Uses curl to probe the top ports. Set TARGET at the top to the Port Leak Checker host. One target per run.

#!/bin/sh
# Enter the Port Leak Checker host below (IP or hostname).
TARGET="portleak.link"
for port in 7 9 13 21 22 23 25 26 37 53 79 80 81 88 106 110 111 112 113 \
            119 135 139 143 144 179 199 389 427 443 444 445 465 513 514 \
            515 543 544 548 554 587 631 646 873 990 993 995 1025 1026 \
            1027 1028 1029 1110 1433 1720 1723 1755 1900 2000 2001 2049 \
            2121 2717 3000 3128 3306 3389; do
    echo "Connecting to port: $port"
    curl -I --connect-timeout 5 --max-time 3 "$TARGET:$port"
done