Port 21801Safe AutoLogon

TCP port 21801 is assigned to Safe AutoLogon, registered by WM Software Inc.; its protocol and deployment are not established.

transport
tcp

single transport

in transit
cleartext

payload readable on path

assignment
official

registered with iana

risk
1/10

safe

lookups
0

rank 993 of 6,404 · top 15%

also known as sal

Technical Details

what runs on :21801

Safe AutoLogon is registered on port :21801 over tcp to WM Software Inc., assigned July 2022. We don't have a technical write-up for it beyond the IANA registry entry.

In nmap's internet-wide scan data this port is never observed open, so if it's open on your network it's more likely a custom or misconfigured service than the registered one.

find what's listening on :21801

this machine
# linux
sudo ss -tlpn 'sport = :21801'

# macos / bsd
sudo lsof -nP -i :21801

# windows (then: tasklist /FI "PID eq <pid>")
netstat -ano | findstr :21801
another host
nmap -sV -p T:21801 <host>

run it? the handshake, the implementations you meet in the wild and the flags that matter come from the engineers who do.

add technical details

Security Information

exposure of :21801

risk score

1/ 10safe

routine exposure. this port is rarely the way in on its own — keep it patched and logged and move on.

in transit

cleartext

credentials and payloads are readable by anyone on path

assignment

official

registered with iana for this service — scanners fingerprint it by number

reachable over

tcp

every listening transport is another surface to filter at the edge

security overview

no security notes recorded for :21801 yet

known exploits, hardening advice, what a compromise looks like — suggest an edit if you know its exposure.

ports registered around :21801, by lookups.

portservicerisk
:21800TVNC Pro Multiplexingsafe
:21847NetSpeak Corp. Connection Servicessafe
:21845webphonesafe

risk mix of the 3 listed

  • safe100%

0 of 3 encrypted