Port 21213Cohesity backup agent

TCP port 21213 is assigned to Cohesity backup agents used with Cohesity data protection products.

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 cohesity-agent

Technical Details

what runs on :21213

Cohesity backup agent is registered on port :21213 over tcp to Cohesity Inc, assigned August 2019. 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 :21213

this machine
# linux
sudo ss -tlpn 'sport = :21213'

# macos / bsd
sudo lsof -nP -i :21213

# windows (then: tasklist /FI "PID eq <pid>")
netstat -ano | findstr :21213
another host
nmap -sV -p T:21213 <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 :21213

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 :21213 yet

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

ports registered around :21213, by lookups.

portservicerisk
:21212Trinket Agentsafe
:21221Air Server servicessafe

risk mix of the 2 listed

  • safe100%

0 of 2 encrypted