CVE-2021-42756

CriticalCVSS 9.8/10Last modified Jun 17, 2026

Description

Multiple stack-based buffer overflow vulnerabilities [CWE-121] in the proxy daemon of FortiWeb 5.x all versions, 6.0.7 and below, 6.1.2 and below, 6.2.6 and below, 6.3.16 and below, 6.4 all versions may allow an unauthenticated remote attacker to achieve arbitrary code execution via specifically crafted HTTP requests.

Metrics

CVSS 3.1 9.8/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness enumeration

CWE-121CWE-787

Affected software

VendorProductVersions
FortinetFortiWeb>= 6.4.0, <= 6.4.1; >= 6.3.0, <= 6.3.16; >= 6.2.0, <= 6.2.6; >= 6.1.0, <= 6.1.2; >= 6.0.0, <= 6.0.7; >= 5.9.0, <= 5.9.1; >= 5.8.5, <= 5.8.7; >= 5.8.0, <= 5.8.3; >= 5.7.0, <= 5.7.3; >= 5.6.0, <= 5.6.2; >= 5.8.0, < 5.8.*; >= 5.7.0, < 5.7.*; >= 5.6.0, < 5.6.*

References

Timeline

Published
Feb 16, 2023
Last modified
Jun 17, 2026
NVD status
Modified

Related CVEs from 2021

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