Port 5603A1-BS
A1-BS is an obscure IANA service assignment on TCP and UDP port 5603 with no established public use.
- transport
- tcp · udp
- in transit
- cleartext
- assignment
- official
- risk
- 1/10
- lookups
- 0
2 transports registered
payload readable on path
registered with iana
safe
rank 993 of 5,528 · top 18%
Technical Details
what runs on :5603A1-BS is registered on port :5603 over tcp and udp to Mike Dolan. 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 :5603
# linux
sudo ss -tulpn 'sport = :5603'
# macos / bsd
sudo lsof -nP -i :5603
# windows (then: tasklist /FI "PID eq <pid>")
netstat -ano | findstr :5603nmap -sV -p T:5603 <host>
sudo nmap -sU -sV -p U:5603 <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 detailsSecurity Information
exposure of :5603risk 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 · udp
udp is connectionless — source addresses are trivially spoofed and it is a reflection favourite
security overview
no security notes recorded for :5603 yet
known exploits, hardening advice, what a compromise looks like — suggest an edit if you know its exposure.
Related Ports
ports registered around :5603, by lookups.
| port | service | risk | |||
|---|---|---|---|---|---|
| :5555 | Freeciv | TCP | Security | caution | 26.9k |
| :5666 | NRPE | TCP | Network Services | caution | 13.6k |
| :5632 | pcAnywhere Status | UDP | Security | caution | 13.4k |
| :5631 | Symantec pcAnywhere | TCP | Security | caution | 10.3k |
| :5667 | NSCA | TCP | Network Services | caution | 8.6k |
| :5656 | IBM Sametime P2P | TCP | File Transfer | safe | 8.5k |
| :5550 | HP Data Protector | TCP | File Transfer | caution | 8.2k |
| :5591 | Tidal Scheduler Master | TCP | System | caution | 6.9k |
risk mix of the 8 listed
- safe13%
- caution88%
0 of 8 encrypted