Beglebone Black img send Email automaticaly on port 25

Please share your test, a new board isn’t going to change anything, the image has the defaults

debian@BeagleBone:~$ cat /etc/dogtag 
BeagleBoard.org Debian Bullseye IoT Image 2023-09-02
debian@BeagleBone:~$ netstat -lntu
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State      
tcp        0      0 127.0.0.1:2947          0.0.0.0:*               LISTEN     
tcp        0      0 0.0.0.0:5355            0.0.0.0:*               LISTEN     
tcp        0      0 0.0.0.0:80              0.0.0.0:*               LISTEN     
tcp        0      0 127.0.0.53:53           0.0.0.0:*               LISTEN     
tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN     
tcp6       0      0 ::1:2947                :::*                    LISTEN     
tcp6       0      0 :::5355                 :::*                    LISTEN     
tcp6       0      0 :::80                   :::*                    LISTEN     
tcp6       0      0 :::22                   :::*                    LISTEN     
udp        0      0 0.0.0.0:5353            0.0.0.0:*                          
udp        0      0 0.0.0.0:5355            0.0.0.0:*                          
udp        0      0 127.0.0.53:53           0.0.0.0:*                          
udp        0      0 192.168.3.206:68        0.0.0.0:*                          
udp        0      0 0.0.0.0:43855           0.0.0.0:*                          
udp6       0      0 :::5353                 :::*                               
udp6       0      0 :::5355                 :::*                               
udp6       0      0 :::46439                :::*

now having fun with tshark, how to filter ARP 60… (ssh i’m ssh’ed in…)

sudo tshark -i eth0 not port 22

ps, probably going to add tshark to default install…

Update, running for…

debian@BeagleBone:~$ uptime -p
up 2 hours, 22 minutes

no traffic over port 25… i think you have a bigger problem ‘inside’ your network from something else… (at-least change the default debian password and root password)

Regards,

I think you’re right.
In fact we found that the IP 192.168.1.14 is already online, intermittently. I didn’t have time today to find out who it is but I’ll find out on Monday morning.
Thanks
I’ll let you know