CVE-2020-12063: Medium severity postfix vulnerability

Published Apr 24, 2020
·
Updated

DISPUTED A certain Postfix 2.10.1-7 package could allow an attacker to send an email from an arbitrary-looking sender via a homoglyph attack, as demonstrated by the similarity of \xce\xbf to the 'o' character. This is potentially relevant when the /etc/postfix/senderlogin feature is used, because a spoofed outbound message that uses a configured sender address is blocked with a "Sender address rejected: not logged in" error message, but a spoofed outbound message that uses a homoglyph of a configured sender address is not blocked. NOTE: some third parties argue that any missed blocking of spoofed outbound messages - except for exact matches to a sender address in the /etc/postfix/senderlogin file - is outside the design goals of Postfix and thus cannot be considered a Postfix vulnerability.

Affected Software

1 affected component
Postfix Postfix=2.10.1

Event History

Apr 24, 2020
CVE Published
via MITRE·11:59 AM
Data Sourced
via MITRE·11:59 AM
Description
Disputed
12:15 PM

Frequently Asked Questions

1

What is the severity of CVE-2020-12063?

The severity of CVE-2020-12063 is medium with a CVSS score of 5.3.

2

How can an attacker exploit CVE-2020-12063?

An attacker can exploit CVE-2020-12063 by sending an email from an arbitrary-looking sender using a homoglyph attack.

3

Which version of Postfix is affected by CVE-2020-12063?

Postfix version 2.10.1 is affected by CVE-2020-12063.

4

What is a homoglyph attack?

A homoglyph attack is a type of attack where an attacker uses characters that look similar to legitimate characters to deceive or trick users.

5

Where can I find more information about CVE-2020-12063?

You can find more information about CVE-2020-12063 at the following references: [Link 1](https://www.openwall.com/lists/oss-security/2020/04/23/12) and [Link 2](https://www.openwall.com/lists/oss-security/2020/04/23/3).

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