CVE-2022-26122: Evasion by manipulating MIME attachment

Published Nov 1, 2022
·
Updated

An insufficient verification of data authenticity vulnerability [CWE-345] in FortiClient, FortiMail and FortiOS AV engines may allow an attacker to bypass the AV engine via manipulating MIME attachment with junk and pad characters in base64.

Other sources

An insufficient verification of data authenticity vulnerability [CWE-345] in FortiClient, FortiMail and FortiOS AV engines version 6.2.168 and below and version 6.4.274 and below may allow an attacker to bypass the AV engine via manipulating MIME attachment with junk and pad characters in base64.

Affected Software

24 affected components
Fortinet Antivirus Engine=0.4.23
Fortinet Antivirus Engine=2.0.49
Fortinet Antivirus Engine=2.0.60
Fortinet Antivirus Engine=4.4.54
Fortinet Antivirus Engine=6.33
Fortinet Antivirus Engine=6.137
Fortinet Antivirus Engine=6.142
Fortinet Antivirus Engine=6.144
Fortinet Antivirus Engine=6.145
Fortinet Antivirus Engine=6.156
Fortinet Antivirus Engine=6.157
Fortinet Antivirus Engine=6.243
Fortinet Antivirus Engine=6.252
Fortinet Antivirus Engine=6.253
Fortinet FortiMail>=6.0.0<=6.0.12
Fortinet FortiMail>=6.2.0<=6.2.9
Fortinet FortiMail>=6.4.0<=6.4.6
Fortinet FortiMail>=7.0.0<=7.0.2
Fortinet FortiMail=4.1.0
Fortinet FortiOS>=6.0.0<=6.0.15
Fortinet FortiOS>=6.2.0<=6.2.11
Fortinet FortiOS>=6.4.0<=6.4.10
Fortinet FortiOS>=7.0.0<=7.0.6
Fortinet FortiOS=7.2.0

Event History

Nov 1, 2022
Advisory Published
via FortiGuard·12:00 AM
Data Sourced
via FortiGuard·12:00 AM
DescriptionSeverityWeaknessAffected Software
Nov 2, 2022
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
DescriptionSeverityWeakness
Oct 25, 2024
Advisory Published
via FortiGuard·12:00 AM
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Frequently Asked Questions

1

What is CVE-2022-26122 vulnerability?

CVE-2022-26122 is an insufficient verification of data authenticity vulnerability in FortiClient, FortiMail, and FortiOS AV engines.

2

What is the severity of CVE-2022-26122?

The severity of CVE-2022-26122 vulnerability is high with a CVSS score of 8.6.

3

Which software versions are affected by CVE-2022-26122?

FortiClient AV engines version 6.2.168 and below, FortiClient 6.4.274 and below, FortiMail version 6.0.0 to 6.0.12, 6.2.0 to 6.2.9, 6.4.0 to 6.4.6, and FortiOS version 6.0.0 to 6.0.15, 6.2.0 to 6.2.11, 6.4.0 to 6.4.10 are affected by CVE-2022-26122.

4

How can an attacker exploit CVE-2022-26122 vulnerability?

An attacker can exploit CVE-2022-26122 vulnerability by manipulating MIME attachment with junk and pad characters in base64.

5

Is there a fix available for CVE-2022-26122 vulnerability?

Yes, Fortinet has released patches to address CVE-2022-26122 vulnerability. It is recommended to update to the latest version of the affected software.

Contact

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