Is CVE-2021-26099 being actively exploited?

CVE-2021-26099 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

What is the CVSS score for CVE-2021-26099?

CVE-2021-26099 has a CVSS 3.1 base score of 4.4 (MEDIUM).

CVE-2021-26099

MEDIUM · CVSS 4.4EPSS 0.5%EU EUVD

Missing cryptographic steps in the Identity-Based Encryption service of FortiMail before 7.0.0 may allow an attacker who comes in possession of the encrypted master keys to compromise their confidentiality by observing a few invariant properties of the ciphertext.

Key facts

CVSS score: 4.4 (v3.1)
Severity: MEDIUM
CVSS vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:N/A:N
EPSS score: 0.5% (44th percentile)
In CISA KEV: No
In EU EUVD: Yes (EUVD-2021-12920)
Published: July 12, 2021
NVD last modified: June 17, 2026
Status: Modified

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2021-12920 in the EU Vulnerability Database. Last updated in EUVD on October 25, 2024.

View on the EU Vulnerability Database

Affected products

fortinet / fortimail

Certified products that may be affected

6 FIPS 140 or Common Criteria certified products, from automated matching by sec-certs.org.

FortiMail 6.0 - Fortinet, Inc. - FIPS 140 3380 - historical
FortiMail-2000E/3000E - Fortinet, Inc. - FIPS 140 3363 - historical
Fortinet FortiMail 6.0 - Fortinet, Inc. - Common Criteria CCEVS-VR-10899-2019 - archived
FortiMail 5.2 - Fortinet, Inc. - FIPS 140 2539 - historical
FortiMail-1000D and FortiMail-3000D - Fortinet, Inc. - FIPS 140 2540 - historical

See all 6 in the Security Certifications Explorer.

References

https://fortiguard.com/advisory/FG-IR-20-244(Vendor Advisory)

Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS

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