#VU54791 Missing Required Cryptographic Step in Fortinet FortiMail - CVE-2021-26099

Vulnerability identifier: #VU54791

Vulnerability risk: Low

CVSSv4.0: 2.1 [CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-26099

CWE-ID: CWE-325

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Fortinet FortiMail
Server applications / IDS/IPS systems, Firewalls and proxy servers

Vendor: Fortinet, Inc

Description

The vulnerability allows a remote attacker to gain access to sensitive information.

The vulnerability exists due to missing cryptographic steps in FortiMail IBE. A remote attacker who comes in possession of the encrypted master keys can compromise their confidentiality by observing a few invariant properties of the ciphertext.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Fortinet FortiMail: 5.0 - 6.4.4

---

External links
https://fortiguard.com/advisory/FG-IR-20-244

---

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated privileged user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.