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Vulnerability record · CVE-2021-36166 · published 1 March 2022

CVE-2021-36166: Fortinet fortimail vulnerability

Fortinet · Fortimail

An improper authentication vulnerability in FortiMail before 7.0.1 may allow a remote attacker to efficiently guess one administrative account's authentication token by means of the observation of certain system's properties.

9.8 CVSS 3.1 Critical EPSS 1.5% · top 27.3% CWE-330 · CWE-330
9.8CVSS 3.1 base score, v2 7.5
1.5%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References
17 Jun 2026Last modified by NVD

Description

An improper authentication vulnerability in FortiMail before 7.0.1 may allow a remote attacker to efficiently guess one administrative account's authentication token by means of the observation of certain system's properties.

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

Affected products

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

References

LinkTags
https://fortiguard.com/psirt/FG-IR-21-028 Vendor Advisory
https://fortiguard.com/psirt/FG-IR-21-028 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-2021-36166), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.