medium
6.7
CWE
787 119
Advisory Published
CVE Published
Advisory Published
Updated

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

First published: Tue Dec 07 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.

Credit: psirt@fortinet.com

Affected SoftwareAffected VersionHow to fix
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-200d>=5.4.0<=6.2.7
Fortinet Fortimail-200d>=6.4.0<=6.4.6
Fortinet Fortimail-200d>=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<=6.2.8
Fortinet FortiOS=6.4.2
Fortinet FortiOS=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 Enterprise>=6.0.0<=6.0.10
Fortinet FortiVoice Enterprise>=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 IPS Engine>=5.0.0<=6.0.13
Fortinet FortiOS IPS Engine>=6.2.0<=6.2.9
Fortinet FortiOS IPS Engine>=6.4.0<=6.4.7
Fortinet FortiOS IPS Engine>=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 Enterprise>=6.0.0<=6.0.10
Fortinet FortiVoice Enterprise>=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-F>=5.5.0<=5.5.1
Fortinet FortiDDoS-F>=5.4
Fortinet FortiDDoS-F>=5.3
Fortinet FortiDDoS-F>=5.2
Fortinet FortiDDoS-F>=5.1
Fortinet FortiDDoS-F>=5.0
Fortinet FortiDDoS-F>=4.7
Fortinet FortiDDoS-F>=4.6
Fortinet FortiDDoS-F>=4.5
Fortinet FortiDDoS-F>=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-200d>=7.0.0<=7.0.2
Fortinet Fortimail-200d>=6.4.0<=6.4.6
Fortinet Fortimail-200d>=6.2.0<=6.2.7
Fortinet Fortimail-200d>=6.0
Fortinet Fortimail-200d>=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 IPS Engine>=7.0.0<=7.0.2
Fortinet FortiOS IPS Engine>=6.4.0<=6.4.7
Fortinet FortiOS IPS Engine>=6.2.0<=6.2.9
Fortinet FortiOS IPS Engine>=6.0.0<=6.0.13
Fortinet FortiOS IPS Engine>=5.6
Fortinet FortiOS IPS Engine>=5.4
Fortinet FortiOS IPS Engine>=5.2
Fortinet FortiOS IPS Engine>=5.0
Fortinet FortiOS=.
Fortinet FortiOS>=6.2.6<=6.2.7
Fortinet FortiOS=.
Fortinet FortiOS>=6.0.12<=6.0.17
Fortinet FortiOS=.
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 400D>=6.4.0<=6.4.2
Fortinet FortiRecorder 400D>=6.0.0<=6.0.10
Fortinet FortiRecorder 400D>=2.7.0<=2.7.7
Fortinet FortiRecorder 400D>=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 Enterprise>=6.4.0<=6.4.4
Fortinet FortiVoice Enterprise>=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

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Reference Links

Frequently Asked Questions

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

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

  • 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.

  • 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.

  • 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.

  • 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.

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