diff --git a/net_alerter/net_alerter.py b/net_alerter/net_alerter.py
index 790b7e0..da6fc19 100644
--- a/net_alerter/net_alerter.py
+++ b/net_alerter/net_alerter.py
@@ -64,7 +64,7 @@ def scan_subnet(cidr: str) -> list[dict]:
     """Run nmap ping scan, return list of {ip, mac, name}."""
     try:
         out = subprocess.check_output(
-            ["nmap", "-sn", "-PR", "--host-timeout", "5s", cidr],
+            ["sudo", "nmap", "-sn", "-PR", "--host-timeout", "5s", cidr],
             text=True, stderr=subprocess.DEVNULL
         )
     except Exception: