MTA Open Mail Relaying Allowed
high Nessus Plugin ID 10262
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Synopsis
An open SMTP relay is running on the remote host.Description
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.
Solution
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: High
ID: 10262
File Name: smtp_relay.nasl
Version: 1.63
Type: remote
Family: SMTP problems
Published: 6/22/1999
Updated: 10/11/2019
Dependencies: smtpserver_detect.nasl, sendmail_expn.nasl, smtp_settings.nasl
Risk Information
CVSS Score Source: CVE-1999-0512
VPR
Risk Factor: Medium
Score: 5.9
CVSS v2
Risk Factor: Critical
Base Score: 10
Temporal Score: 8.5
Vector: AV:N/AC:L/Au:N/C:C/I:C/A:C
Temporal Vector: E:U/RL:ND/RC:C
CVSS v3
Risk Factor: High
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: E:U/RL:X/RC:C
Vulnerability Information
Excluded KB Items: SMTP/wrapped, SMTP/qmail
Exploit Ease: No known exploits are available
Vulnerability Publication Date: 1/1/1990