Port 25 SMTP
Simple Mail Transfer Protocol
About Port 25
SMTP is the standard protocol for sending email messages between servers. Port 25 is used for server-to-server mail relay and delivery.
Security Notes
Open SMTP relays can be abused for spam. Ensure proper authentication (SMTP AUTH) and encryption (STARTTLS) are configured. Consider using port 587 for mail submission.
Total Hosts
21.0M
TLS Encrypted
0.0%
Vulnerable Hosts
2.3M
Countries
10+
Top Services
| smtp | 20,691,537 |
| http | 98,403 |
| ftp | 86,287 |
| smtp-proxy | 62,910 |
| unknown | 45,947 |
| telnet | 16,460 |
| ssh | 15,872 |
| mysql | 2,440 |
| socks4 | 2,159 |
| mongodb | 1,747 |
Top Countries
 United States |
3,366,210 |
 Germany |
2,877,119 |
 France |
1,644,592 |
 Japan |
1,320,224 |
 Netherlands |
938,163 |
 United Kingdom |
813,664 |
 Canada |
464,095 |
 Russia |
407,828 |
 Romania |
352,764 |
 Austria |
338,392 |
Top Products
| Postfix smtpd | 9,191,125 |
| Exim smtpd | 2,253,168 |
| cbdev cmail smtpd | 962,322 |
| Sendmail | 525,805 |
| Microsoft Exchange smtpd | 461,582 |
| ESMTP | 432,610 |
| MailEnable smptd | 258,932 |
| Exim | 113,574 |
| Proxy | 97,579 |
| Microsoft ESMTP | 86,356 |