Port 996vsinet

The vsinet service is assigned to TCP and UDP port 996, but its protocol purpose is not documented.

transport
tcp · udp

2 transports registered

in transit
cleartext

payload readable on path

assignment
official

registered with iana

risk
1/10

safe

lookups
0

rank 993 of 4,578 · top 22%

Technical Details

what runs on :996

vsinet is registered on port :996 over tcp and udp to Rob Juergens. 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 found open very commonly. What's listening is often not the registered service, so check before you assume.

find what's listening on :996

this machine
# linux
sudo ss -tulpn 'sport = :996'

# macos / bsd
sudo lsof -nP -i :996

# windows (then: tasklist /FI "PID eq <pid>")
netstat -ano | findstr :996
another host
nmap -sV -p T:996 <host>
sudo nmap -sU -sV -p U:996 <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 :996

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 · udp

udp is connectionless — source addresses are trivially spoofed and it is a reflection favourite

security overview

no security notes recorded for :996 yet

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

ports registered around :996, by lookups.

portservicerisk
:981Check Point Embedded HTTPS Managementcaution
:992Telnet over TLS/SSLcaution
:989FTPS Datacaution
:990FTPS Controlcaution
:995POP3Scaution
:991Netnews Administration Systemcaution
:953DNS RNDCsafe
:1059IBM AIX NIMcaution

risk mix of the 8 listed

  • safe13%
  • caution88%

5 of 8 encrypted