To change the security engine default port (8080) you must edit 2 configuration files:

Linux

$> vim /etc/crowdsec/config.yaml

Within the config.yaml you will find the following line:

api:
 server:
   listen_uri: 127.0.0.1:8080 # CHANGE this line to the port you wish to listen on

Once saved you must then configure the local_api_credentials file to the same port

$> vim /etc/crowdsec/local_api_credentials.yaml

Within the file change the following line:

url: http://127.0.0.1:8080 # CHANGE this line to the same port as you configured above
login: ...
password: ...

Freebsd

$> vim /usr/local/etc/crowdsec/config.yaml

Within the config.yaml you will find the following line:

api:
 server:
   listen_uri: 127.0.0.1:8080 # CHANGE this line to the port you wish to listen on

Once saved you must then configure the local_api_credentials file to the same port

$> vim /usr/local/etc/crowdsec/local_api_credentials.yaml

Within the file change the following line:

url: http://127.0.0.1:8080 # CHANGE this line to the same port as you configured above
login: ...
password: ...

You must run these commands in an elevated powershell prompt.

$> notepad c:/programdata/crowdsec/config/config.yaml

Within the config.yaml you will find the following line:

api:
 server:
   listen_uri: 127.0.0.1:8080 # CHANGE this line to the port you wish to listen on

Once saved you must then configure the local_api_credentials file to the same port

$> notepad c:/programdata/crowdsec/config/local_api_credentials.yaml

Within the file change the following line:

url: http://127.0.0.1:8080 # CHANGE this line to the same port as you configured above
login: ...
password: ...