Rapid7 Vulnerability & Exploit Database

SMTP unauthenticated 3rd-party mail relay (from percent)

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SMTP unauthenticated 3rd-party mail relay (from percent)

Severity
10
CVSS
(AV:N/AC:L/Au:N/C:C/I:C/A:C)
Published
01/01/1999
Created
07/25/2018
Added
11/01/2004
Modified
03/21/2018

Description

While your mailer rejects 3rd-party relay in some cases, it allows mail to be relayed if the client issues a "MAIL FROM:" command with an address consisting only of a single percent sign. This could be a configuration error, or a bug in the mail server.

Solution(s)

  • smtp-disable-relay

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