CVE-2021-42757: Buffer overflow in TFTP client library of CLI

Published Dec 7, 2021
·
Updated

A buffer overflow [CWE-121] in the TFTP client library of FortiOS before 6.4.7 and FortiOS 7.0.0 through 7.0.2, may allow an authenticated local attacker to achieve arbitrary code execution via specially crafted command line arguments.

Other sources

A buffer overflow [CWE-121] in the TFTP client library of FortiOS, may allow an authenticated local attacker to achieve arbitrary code execution via specially crafted command line arguments.

— FortiGuard

Affected Software

120 affected componentsFixes available
Fortinet FortiADC>=5.0.0<=6.1.5
Fortinet FortiADC>=6.2.0<=6.2.2
Fortinet FortiAnalyzer>=6.0.0<=6.4.7
Fortinet FortiAnalyzer>=7.0.0<=7.0.2
Fortinet FortiMail>=5.4.0<=6.2.7
Fortinet FortiMail>=6.4.0<=6.4.6
Fortinet FortiMail>=7.0.0<=7.0.2
Fortinet FortiManager>=6.0.0<=6.4.7
Fortinet FortiManager>=7.0.0<=7.0.2
Fortinet FortiNDR>=1.1.0<=1.5.2
Fortinet FortiOS-6K7K<=6.2.8
Fortinet FortiOS-6K7K=6.4.2
Fortinet FortiOS-6K7K=6.4.6
Fortinet FortiPortal>=5.0.0<=6.0.10
Fortinet FortiProxy>=1.0.0<=2.0.7
Fortinet FortiProxy=7.0.0
Fortinet FortiProxy=7.0.1
Fortinet FortiVoice>=6.0.0<=6.0.10
Fortinet FortiVoice>=6.4.0<=6.4.4
Fortinet FortiWeb>=5.0.0<=6.3.16
Fortinet FortiWeb=6.4.0
Fortinet FortiWeb=6.4.1
Fortinet FortiOS>=5.0.0<=6.0.13
Fortinet FortiOS>=6.2.0<=6.2.9
Fortinet FortiOS>=6.4.0<=6.4.7
Fortinet FortiOS>=7.0.0<=7.0.2
Fortinet Fortirecorder Firmware>=2.6.0<=6.0.10
Fortinet Fortirecorder Firmware>=6.4.0<=6.4.2
Fortinet FortiSwitch>=6.0.0<=6.4.9
Fortinet FortiSwitch>=7.0.0<=7.0.3
Fortinet FortiVoice>=6.0.0<=6.0.10
Fortinet FortiVoice>=6.4.0<=6.4.4
Fortinet FortiADC>=6.2.0<=6.2.2
Fortinet FortiADC>=6.1.0<=6.1.5
Fortinet FortiADC>=6.0
Fortinet FortiADC>=5.4
Fortinet FortiADC>=5.3
Fortinet FortiADC>=5.2
Fortinet FortiADC>=5.1
Fortinet FortiADC>=5.0
Fortinet FortiAnalyzer>=7.0.0<=7.0.2
Fortinet FortiAnalyzer>=6.4.0<=6.4.7
Fortinet FortiAnalyzer>=6.2
Fortinet FortiAnalyzer>=6.0
Fortinet FortiDDoS>=5.5.0<=5.5.1
Fortinet FortiDDoS>=5.4
Fortinet FortiDDoS>=5.3
Fortinet FortiDDoS>=5.2
Fortinet FortiDDoS>=5.1
Fortinet FortiDDoS>=5.0
Fortinet FortiDDoS>=4.7
Fortinet FortiDDoS>=4.6
Fortinet FortiDDoS>=4.5
Fortinet FortiDDoS>=4.4
Fortinet FortiDDoS-F>=6.4.0<=6.4.1
Fortinet FortiDDoS-F=.
Fortinet FortiDDoS-F>=6.2.0<=6.2.2
Fortinet FortiDDoS-F>=6.1.0<=6.1.4
Fortinet FortiMail>=7.0.0<=7.0.2
Fortinet FortiMail>=6.4.0<=6.4.6
Fortinet FortiMail>=6.2.0<=6.2.7
Fortinet FortiMail>=6.0
Fortinet FortiMail>=5.4
Fortinet FortiManager>=7.0.0<=7.0.2
Fortinet FortiManager>=6.4.0<=6.4.7
Fortinet FortiManager>=6.2
Fortinet FortiManager>=6.0
Fortinet FortiNDR>=1.5.0<=1.5.2
Fortinet FortiNDR>=1.4
Fortinet FortiNDR>=1.3
Fortinet FortiNDR>=1.2
Fortinet FortiNDR>=1.1
Fortinet FortiOS>=7.0.0<=7.0.2
Fortinet FortiOS>=6.4.0<=6.4.7
Fortinet FortiOS>=6.2.0<=6.2.9
Fortinet FortiOS>=6.0.0<=6.0.13
Fortinet FortiOS>=5.6
Fortinet FortiOS>=5.4
Fortinet FortiOS>=5.2
Fortinet FortiOS>=5.0
Fortinet FortiOS-6K7K=.
Fortinet FortiOS-6K7K>=6.2.6<=6.2.7
Fortinet FortiOS-6K7K=.
Fortinet FortiOS-6K7K>=6.0.12<=6.0.17
Fortinet FortiOS-6K7K=.
Fortinet FortiPortal>=6.0.0<=6.0.10
Fortinet FortiPortal>=5.3
Fortinet FortiPortal>=5.2
Fortinet FortiPortal>=5.1
Fortinet FortiPortal>=5.0
Fortinet FortiProxy>=7.0.0<=7.0.1
Fortinet FortiProxy>=2.0.0<=2.0.7
Fortinet FortiProxy>=1.2
Fortinet FortiProxy>=1.1
Fortinet FortiProxy>=1.0
Fortinet FortiRecorder>=6.4.0<=6.4.2
Fortinet FortiRecorder>=6.0.0<=6.0.10
Fortinet FortiRecorder>=2.7.0<=2.7.7
Fortinet FortiRecorder>=2.6
Fortinet FortiSwitch>=7.0.0<=7.0.3
Fortinet FortiSwitch>=6.4.0<=6.4.9
Fortinet FortiSwitch>=6.2.0<=6.2.7
Fortinet FortiSwitch>=6.0
Fortinet FortiVoice>=6.4.0<=6.4.4
Fortinet FortiVoice>=6.0.0<=6.0.10
Fortinet FortiWeb>=6.4.0<=6.4.1
Fortinet FortiWeb>=6.3.0<=6.3.16
Fortinet FortiWeb>=6.2
Fortinet FortiWeb>=6.1
Fortinet FortiWeb>=6.0
Fortinet FortiWeb>=5.9
Fortinet FortiWeb>=5.8
Fortinet FortiWeb>=5.7
Fortinet FortiWeb>=5.6
Fortinet FortiWeb>=5.5
Fortinet FortiWeb>=5.4
Fortinet FortiWeb>=5.3
Fortinet FortiWeb>=5.2
Fortinet FortiWeb>=5.1
Fortinet FortiWeb>=5.0

Remediation

Information

Upgrade to FortiOS version 7.0.3 or above Upgrade to FortiOS version 6.4.8 or above Upgrade to FortiOS version 6.2.10 or above Upgrade to FortiOS version 6.0.14 or above Upgrade to FortiDDoS-F version 6.4.2 or above Upgrade to FortiDDoS-F version 6.3.1 or above Upgrade to FortiDDoS-F version 6.2.3 or above Upgrade to FortiDDoS-F version 6.1.5 or above Upgrade to FortiOS-6K7K version 6.4.8 or above Upgrade to FortiOS-6K7K version 6.2.9 or above Upgrade to FortiVoice version 6.4.5 or above Upgrade to FortiVoice version 6.0.11 or above Upgrade to FortiProxy version 7.0.2 or above Upgrade to FortiProxy version 2.0.8 or above Upgrade to FortiRecorder version 7.0.0 or above Upgrade to FortiRecorder version 6.4.3 or above Upgrade to FortiRecorder version 6.0.11 or above Upgrade to upcoming FortiRecorder version 2.7.8 or above Upgrade to FortiPortal version 6.0.11 or above Upgrade to FortiMail version 7.2.0 or above Upgrade to FortiMail version 7.0.3 or above Upgrade to FortiMail version 6.4.7 or above Upgrade to FortiAnalyzer version 7.0.3 or above Upgrade to FortiAnalyzer version 6.4.8 or above Upgrade to FortiNDR version 7.0.0 or above Upgrade to FortiDDoS version 5.6.0 or above Upgrade to FortiDDoS version 5.5.2 or above Upgrade to FortiSwitch version 7.2.0 or above Upgrade to FortiSwitch version 7.0.4 or above Upgrade to FortiSwitch version 6.4.10 or above Upgrade to FortiADC version 7.0.1 or above Upgrade to FortiADC version 6.2.3 or above Upgrade to FortiADC version 6.1.6 or above Upgrade to FortiWeb version 7.0.0 or above Upgrade to FortiWeb version 6.4.2 or above Upgrade to FortiWeb version 6.3.17 or above Upgrade to FortiManager version 7.0.3 or above Upgrade to FortiManager version 6.4.8 or above

Event History

Dec 7, 2021
Advisory Published
via FortiGuard·12:00 AM
Dec 8, 2021
CVE Published
via MITRE·11:01 AM
Data Sourced
via MITRE·11:01 AM
RemedyDescriptionSeverityWeakness
Data Sourced
via NVD·11:15 AM
DescriptionSeverityWeaknessAffected Software
Oct 25, 2024
Advisory Published
via FortiGuard·12:00 AM
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Frequently Asked Questions

1

What is the vulnerability ID for this FortiOS buffer overflow vulnerability?

The vulnerability ID for this FortiOS buffer overflow is CVE-2021-42757.

2

What is the severity level of CVE-2021-42757?

The severity level of CVE-2021-42757 is medium with a CVSS score of 6.7.

3

Which software versions are affected by CVE-2021-42757?

CVE-2021-42757 affects FortiOS versions before 6.4.7 and FortiOS 7.0.0 through 7.0.2.

4

How can an attacker exploit CVE-2021-42757?

An authenticated local attacker can exploit CVE-2021-42757 by using specially crafted command line arguments to achieve arbitrary code execution.

5

Is there a fix available for CVE-2021-42757?

Yes, a fix is available for CVE-2021-42757 in FortiOS versions 6.4.7 and 7.0.3.

Company

Resources

Contact

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