CVE-2021-36166: An improper authentication vulnerability in FortiMail before 7.0.1 may allow a remote attacker to efficiently guess one administrative account's authentication…

PriorityP265critical9.8CVSS 3.1

AVNACLPRNUINSUCHIHAH

EPSS

1.45%

70.3th percentile

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.

Affected

7 ranges

Vendor	Product	Version range	Fixed in
fortinet	fortimail	<= 5.4.12	—
fortinet	fortimail	—	—
fortinet	fortimail	—	—
fortinet	fortimail	>= 6.0.0 < 6.0.12	6.0.12
fortinet	fortimail	>= 6.2.0 < 6.2.8	6.2.8
fortinet	fortimail	>= 6.4.0 < 6.4.6	6.4.6
fortinet	fortinet_fortimail	—	—

Detection & IOCsextracted from sources · hover to see the quote

→Target product is FortiMail before version 7.0.1; monitor for repeated or sequential administrative authentication token submissions against FortiMail admin interfaces, which may indicate token guessing/brute-force activity ↗
→CWE-330 (Use of Insufficiently Random Values) — the token is guessable via observable system properties; look for anomalous patterns in admin session token values or high-frequency admin authentication attempts from external IPs ↗

·Vulnerability only affects FortiMail versions prior to 7.0.1; ensure patching to 7.0.1 or later to remediate. Only one administrative account's token is exposed per the advisory. ↗

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P

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