CVE-2021-42757

MEDIUM

6.7

CVSS Score

Published: December 8, 2021 at 11:01 AM UTC

Updated: June 17, 2026 at 04:10 AM UTC

16 products affected across 1 vendorFortiOSFortiProxyFortiWeb

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Severity

MEDIUM6.7

Exploit prediction

EPSS 0.5%

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

FortiADC · Fortinet

95%

5.0.0 ≤ v ≤ 5.0.45.0.0 ≤ v ≤ 6.1.55.1.0 ≤ v ≤ 5.1.75.2.0 ≤ v ≤ 5.2.85.3.0 ≤ v ≤ 5.3.75.4.0 ≤ v ≤ 5.4.56.0.0 ≤ v ≤ 6.0.46.1.0 ≤ v ≤ 6.1.56.2.0 ≤ v ≤ 6.2.25.0.0 5.0.1 5.0.2 5.0.3 5.0.4 5.1.0 5.1.1 5.1.2 5.1.3 5.1.4 5.1.5 5.1.6 5.1.7 5.2.0 5.2.1 5.2.2 5.2.3 5.2.4 5.2.5 5.2.6 5.2.7 5.2.8 5.3.0 5.3.1 5.3.2 5.3.3 5.3.4 5.3.5 5.3.6 5.3.7 5.4.0 5.4.1 5.4.2 5.4.3 5.4.4 5.4.5 6.0.0 6.0.1 6.0.2 6.0.3 6.0.4 6.1.0 6.1.1 6.1.2 6.1.3 6.1.4 6.1.5 6.2.0 6.2.1 6.2.2

FortiAnalyzer · Fortinet

95%

6.0.0 ≤ v ≤ 6.0.126.0.0 ≤ v ≤ 6.4.76.2.0 ≤ v ≤ 6.2.136.4.0 ≤ v ≤ 6.4.77.0.0 ≤ v ≤ 7.0.26.0.0 6.0.1 6.0.10 6.0.11 6.0.12 6.0.2 6.0.3 6.0.4 6.0.5 6.0.6 6.0.7 6.0.8 6.0.9 6.2.0 6.2.1 6.2.10 6.2.11 6.2.12 6.2.13 6.2.2 6.2.3 6.2.4 6.2.5 6.2.6 6.2.7 6.2.8 6.2.9 6.4.0 6.4.1 6.4.2 6.4.3 6.4.4 6.4.5 6.4.6 6.4.7 7.0.0 7.0.1 7.0.2

FortiDDoS · Fortinet

95%

4.4.0 ≤ v ≤ 4.4.25.3.0 ≤ v ≤ 5.3.25.4.0 ≤ v ≤ 5.4.35.5.0 ≤ v ≤ 5.5.14.4.0 4.4.1 4.4.2 4.5.0 4.6.0 4.7.0 5.0.0 5.1.0 5.2.0 5.3.0 5.3.1 5.3.2 5.4.0 5.4.1 5.4.2 5.4.3 5.5.0 5.5.1

FortiDDoS-F · Fortinet

95%

6.1.0 ≤ v ≤ 6.1.46.2.0 ≤ v ≤ 6.2.26.4.0 ≤ v ≤ 6.4.16.1.0 6.1.1 6.1.2 6.1.3 6.1.4 6.2.0 6.2.1 6.2.2 6.3.0 6.4.0 6.4.1

FortiMail · Fortinet

95%

5.4.0 ≤ v ≤ 5.4.125.4.0 ≤ v ≤ 6.2.76.0.0 ≤ v ≤ 6.0.126.2.0 ≤ v ≤ 6.2.76.4.0 ≤ v ≤ 6.4.67.0.0 ≤ v ≤ 7.0.25.4.0 5.4.1 5.4.10 5.4.11 5.4.12 5.4.2 5.4.3 5.4.4 5.4.5 5.4.6 5.4.7 5.4.8 5.4.9 6.0.0 6.0.1 6.0.10 6.0.11 6.0.12 6.0.2 6.0.3 6.0.4 6.0.5 6.0.6 6.0.7 6.0.8 6.0.9 6.2.0 6.2.1 6.2.2 6.2.3 6.2.4 6.2.5 6.2.6 6.2.7 6.4.0 6.4.1 6.4.2 6.4.3 6.4.4 6.4.5 6.4.6 7.0.0 7.0.1 7.0.2

FortiManager · Fortinet

95%

FortiNDR · Fortinet

95%

1.1.0 ≤ v ≤ 1.5.21.3.0 ≤ v ≤ 1.3.11.5.0 ≤ v ≤ 1.5.21.1.0 1.2.0 1.3.0 1.4.0 1.5.0

FortiOS · Fortinet

95%

5.0.0 ≤ v ≤ 5.0.145.0.0 ≤ v ≤ 6.0.135.2.0 ≤ v ≤ 5.2.155.4.0 ≤ v ≤ 5.4.135.6.0 ≤ v ≤ 5.6.146.0.0 ≤ v ≤ 6.0.136.2.0 ≤ v ≤ 6.2.96.4.0 ≤ v ≤ 6.4.77.0.0 ≤ v ≤ 7.0.25.0.0 5.0.1 5.0.10 5.0.11 5.0.12 5.0.13 5.0.14 5.0.2 5.0.3 5.0.4 5.0.5 5.0.6 5.0.7 5.0.8 5.0.9 5.2.0 5.2.1 5.2.10 5.2.11 5.2.12 5.2.13 5.2.14 5.2.15 5.2.2 5.2.3 5.2.4 5.2.5 5.2.6 5.2.7 5.2.8 5.2.9 5.4.0 5.4.1 5.4.10 5.4.11 5.4.12 5.4.13 5.4.2 5.4.3 5.4.4 5.4.5 5.4.6 5.4.7 5.4.8 5.4.9 5.6.0 5.6.1 5.6.10 5.6.11 5.6.12 5.6.13 5.6.14 5.6.2 5.6.3 5.6.4 5.6.5 5.6.6 5.6.7 5.6.8 5.6.9 6.0.0 6.0.1 6.0.10 6.0.11 6.0.12 6.0.13 6.0.2 6.0.3 6.0.4 6.0.5 6.0.6 6.0.7 6.0.8 6.0.9 6.2.0 6.2.1 6.2.2 6.2.3 6.2.4 6.2.5 6.2.6 6.2.7 6.2.8 6.2.9 6.4.0 6.4.1 6.4.2 6.4.3 6.4.4 6.4.5 6.4.6 6.4.7 7.0.0 7.0.1 7.0.2

FortiOS-6K7K · Fortinet

95%

v ≤ 6.2.86.4.2 6.4.6

FortiPortal · Fortinet

95%

5.0.0 ≤ v ≤ 5.0.35.0.0 ≤ v ≤ 6.0.105.1.0 ≤ v ≤ 5.1.25.2.0 ≤ v ≤ 5.2.65.3.0 ≤ v ≤ 5.3.86.0.0 ≤ v ≤ 6.0.105.0.0 5.0.1 5.0.2 5.0.3 5.1.0 5.1.1 5.1.2 5.2.0 5.2.1 5.2.2 5.2.3 5.2.4 5.2.5 5.2.6 5.3.0 5.3.1 5.3.2 5.3.3 5.3.4 5.3.5 5.3.6 5.3.7 5.3.8 6.0.0 6.0.1 6.0.10 6.0.2 6.0.3 6.0.4 6.0.5 6.0.6 6.0.7 6.0.8 6.0.9

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

https://fortiguard.com/advisory/FG-IR-21-173

References (1)

Vendor Advisory

Source: [email protected]

https://fortiguard.com/advisory/FG-IR-21-173

CVSS

6.7MEDIUM[email protected]

Attack Vector: LOCAL
Complexity: LOW
Privileges: HIGH
User Interaction: NONE
Scope: UNCHANGED
Confidentiality: HIGH
Integrity: HIGH
Availability: HIGH

Vector?

Quick Info

StatusMODIFIED

CWE

CWE-787CWE-120

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