MTA Open Mail Relaying Allowed

Critical Nessus Plugin ID 10262


An open SMTP relay is running on the remote host.


Nessus has detected that the remote SMTP server allows mail relaying.
This issue allows any spammer to use your mail server to send their mail to the world, thus flooding your network bandwidth and possibly getting your mail server blacklisted.


Reconfigure your SMTP server so that it cannot be used as an indiscriminate SMTP relay. Make sure that the server uses appropriate access controls to limit the extent to which relaying is possible.

See Also

Plugin Details

Severity: Critical

ID: 10262

File Name: smtp_relay.nasl

Version: 1.63

Type: remote

Published: 1999/06/22

Updated: 2019/10/11

Dependencies: 10249, 10263, 11038

Risk Information

Risk Factor: Critical

CVSS Score Source: CVE-1999-0512

CVSS v2.0

Base Score: 10

Temporal Score: 8.5

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C

Temporal Vector: CVSS2#E:U/RL:ND/RC:C

CVSS v3.0

Base Score: 7.5

Temporal Score: 6.9

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Temporal Vector: CVSS:3.0/E:U/RL:X/RC:C

Vulnerability Information

Excluded KB Items: SMTP/wrapped, SMTP/qmail

Exploit Available: false

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 1990/01/01

Reference Information

CVE: CVE-1999-0512, CVE-2002-1278, CVE-2003-0285

BID: 7580, 8196, 83209