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Vulnerability record · CVE-2021-42757 · published 8 December 2021

CVE-2021-42757: Fortinet fortiadc classic buffer overflow vulnerability

Fortinet · Fortiadc

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.

6.7 CVSS 3.1 Medium EPSS 0.48% · top 61.1% CWE-120 · Classic buffer overflowCWE-787 · Out-of-bounds write
6.7CVSS 3.1 base score, v2 4.6
0.48%EPSS exploitation probability, 30 days
NoNot in CISA KEV
13Affected product versions listed by NVD
2References
17 Jun 2026Last modified by NVD

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.

CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Affected products

13 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

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

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2021-42757), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.