Port 7847 CSOAUTH
Port 7847 is the IANA-assigned csoauth port for A product key authentication protocol made by CSO (TCP).
What is port 7847 used for?
Port 7847 is assigned to csoauth and uses TCP. The IANA registry describes the service as “A product key authentication protocol made by CSO”. It sits in the registered range, the block used by databases, application servers and developer tooling. Port conflicts here are common when several local services start at once.
Ports are the transport-layer address a service listens on. A client that wants to reach csoauth connects to port 7847. If nothing is listening, the connection is refused. That is why a port conflict appears whenever two processes try to bind the same number.
Use the commands below to confirm whether port 7847 is actually in use before you change firewall rules. Blocking the port stops new inbound traffic at the firewall, but it does not stop a local process from listening, and it does not remove the service from the machine.
Browse all Authentication and access ports
Source: IANA Service Name and Transport Protocol Port Number Registry. Registered assignee: [Jeff_Wamsley].
Check and block port 7847
Copy-ready commands for the protocols assigned to this port. Run the check first, then block only what should not be reachable.
Check on Linux
sudo ss -tlpn 'sport = :7847'Check on Windows
Get-NetTCPConnection -LocalPort 7847 -State Listen -ErrorAction SilentlyContinueBlock with UFW
sudo ufw deny 7847/tcpBlock with iptables
sudo iptables -A INPUT -p tcp --dport 7847 -j DROPThese commands are examples for a typical host. Check the listener before you change firewall rules, and persist iptables rules with iptables-save or netfilter-persistent. On Windows, use Windows Defender Firewall or New-NetFirewallRule for persistent blocks. The iptables rules here cover IPv4; mirror them with ip6tables if IPv6 is enabled.
Is port 7847 safe to expose?
This port is not on our curated list of services with a widely exploited profile. Exposure is only safe when the listening service is intended, patched and protected by a firewall. Keep the listening service patched and remove it if unused. A default-deny firewall policy with explicit allow rules is still the safest baseline.
Where port 7847 is usually used
Most traffic on port 7847 falls into these scenarios. The demo below is a safe way to confirm the listener before you change anything.
- Network devices authenticating users through a central service.
- Wi-Fi, VPN and remote-access gateways enforcing access policy.
- Accounting and session logs used for audits.
Probe the auth service
Authentication protocols are sensitive to shared secrets and source addresses, so test from an authorised client.
nc -vz 127.0.0.1 7847Common problems with port 7847
Connection refused or timed out
Refused usually means the host is reachable but nothing is listening on port 7847. A timeout more often means a firewall drop, a wrong host or a service bound to a different interface.
Port already in use
Find the process holding the port with sudo ss -tlpn 'sport = :7847' or sudo lsof -i :7847. Stop that process or configure it to bind another port; killing it without identifying it can take down a production service.
Firewall rule did not survive a reboot
UFW and Windows Firewall keep rules across restarts. Raw iptables rules do not: save them with iptables-save or the netfilter-persistent package, and re-apply after upgrades that reset the ruleset.
The port is blocked but still reachable
A firewall rule filters inbound traffic; it does not close the listener. Confirm with the check command above and bind the service to 127.0.0.1 when only local clients need it.
Port 7847 at a glance
| Port number | 7847 |
|---|---|
| Service name | csoauth |
| Transport protocol | TCP |
| Category | Authentication and access |
| Range | Registered port (1024–10000) |
| Risk level | Standard/Low |
| Registered assignee | [Jeff_Wamsley] |
| Registry description | A product key authentication protocol made by CSO |
| Source | IANA Service Name and Transport Protocol Port Number Registry |
Frequently asked questions
What is port 7847 used for?
Port 7847 (CSOAUTH) uses TCP. A product key authentication protocol made by CSO.
How do I check if port 7847 is open?
On Linux run `sudo ss -tlpn 'sport = :7847'`. On Windows run `Get-NetTCPConnection -LocalPort 7847 -State Listen -ErrorAction SilentlyContinue` in PowerShell. If the port is open, the output shows a process listening on port 7847; empty output usually means nothing is bound to it.
How do I block port 7847?
With UFW run `sudo ufw deny 7847/tcp`. With iptables run `sudo iptables -A INPUT -p tcp --dport 7847 -j DROP`. Persist the iptables rules with your distribution's netfilter-persistent or iptables-save tooling so they survive a reboot.
Is port 7847 safe to expose?
This port is not on our curated list of services with a widely exploited profile. Exposure is only safe when the listening service is intended, patched and protected by a firewall. Nevertheless, keep the listening service patched and remove it if unused. A default-deny firewall policy with explicit allow rules is still the safest baseline.
Related ports
- Port 7810 · rbt-wanoptRiverbed WAN Optimization Protocol
- Port 7869 · mobileanalyzerMobileAnalyzer& MobileMonitor
- Port 7004 · afs3-kaserverAFS/Kerberos authentication service
- Port 27999 · tw-auth-keyTW Authentication/Key Distribution and
- Port 5635 · sfmssoSFM Authentication Subsystem
- Port 4129 · nuauthNuFW authentication protocol
Primary data: IANA Service Name and Transport Protocol Port Number Registry.
Last reviewed 2026-10-30 · Methodology · About · Privacy