Cisco Cisco Email Security Appliance X1070 Fehlerbehebungsanleitung

Contents

Introduction

Prerequisites

Requirements

Components Used

Problem

Solution

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Additional Measures

Introduction

This document describes a problem that is encountered in the Cisco Email Security Appliance
(ESA) when spam and fraudulent email enters into the network. Possible solutions to this problem
are also described.

Prerequisites

Requirements

Cisco recommends that you have knowledge of these topics:

Cisco ESA

●

AsyncOS

●

Components Used

The information in this document is based on these hardware and software versions:

All versions of Cisco ESA

●

All versions of AsyncOS

●

The information in this document was created from the devices in a specific lab environment. All of
the devices used in this document started with a cleared (default) configuration. If your network is
live, make sure that you understand the potential impact of any command.

Problem

Fraudsters attempt to impersonate email. When the email impersonates (purports to be from) a
member of your company staff, it can be particularly deceptive and has the potential to cause
confusion. In an attempt to solve this problem, email administrators might attempt to block inbound
mail that appears to originate from within the company (spoofed mail).

It might seem logical that if you block the inbound mail from the Internet that has the company
return address in the domain name, it solves the problem. Unfortunately, when you block mail in