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Vulnerability record · CVE-2021-43074 · published 16 February 2023

CVE-2021-43074: Fortinet fortiproxy improper verification of cryptographic signature vulnerability

Fortinet · Fortiproxy

An improper verification of cryptographic signature vulnerability [CWE-347] in FortiWeb 6.4 all versions, 6.3.16 and below, 6.2 all versions, 6.1 all versions, 6.0 all versions; FortiOS 7.0.3 and below, 6.4.8 and below, 6.2 all versions, 6.0 all versions; FortiSwitch 7.0.3 and below, 6.4.10 and below, 6.2 all versions, 6.0 all versions; FortiProxy 7.0.1 and below, 2.0.7 and below, 1.2 all versions, 1.1 all versions, 1.0 all versions may allow an attacker to decrypt portions of the administrative session management cookie if able to intercept the latter.

4.3 CVSS 3.1 Medium EPSS 0.29% · top 80.5% CWE-347 · Improper verification of cryptographic signature
4.3CVSS 3.1 base score
0.29%EPSS exploitation probability, 30 days
NoNot in CISA KEV
4Affected product versions listed by NVD
2References
17 Jun 2026Last modified by NVD

Description

An improper verification of cryptographic signature vulnerability [CWE-347] in FortiWeb 6.4 all versions, 6.3.16 and below, 6.2 all versions, 6.1 all versions, 6.0 all versions; FortiOS 7.0.3 and below, 6.4.8 and below, 6.2 all versions, 6.0 all versions; FortiSwitch 7.0.3 and below, 6.4.10 and below, 6.2 all versions, 6.0 all versions; FortiProxy 7.0.1 and below, 2.0.7 and below, 1.2 all versions, 1.1 all versions, 1.0 all versions may allow an attacker to decrypt portions of the administrative session management cookie if able to intercept the latter.

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

Affected products

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

References

LinkTags
https://fortiguard.com/psirt/FG-IR-21-126 Vendor Advisory
https://fortiguard.com/psirt/FG-IR-21-126 Vendor Advisory

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

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Source: NIST National Vulnerability Database (record CVE-2021-43074), CISA KEV, FIRST EPSS (scores of 2026-10-10). This page is refreshed as NVD updates the record.