How severe is CVE-2021-24012?

CVE-2021-24012 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2021-24012 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-24012?

CVE-2021-24012 affects Fortinet Fortios. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-24012?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-24012 published?

CVE-2021-24012 was published on 2021-06-02 and last updated on 2026-06-17.

CVE-2021-24012

CVE-2021-24012 is a medium-severity vulnerability in Fortinet Fortios with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-295.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 7.5
EPSS exploit prediction: 0% (38th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Fortinet Fortios
Published: 2021-06-02
Last modified: 2026-06-17

Description

An improper following of a certificate's chain of trust vulnerability in FortiGate versions 6.4.0 to 6.4.4 may allow an LDAP user to connect to SSLVPN with any certificate that is signed by a trusted Certificate Authority.

Frequently asked questions

What is CVE-2021-24012?: An improper following of a certificate's chain of trust vulnerability in FortiGate versions 6.4.0 to 6.4.4 may allow an LDAP user to connect to SSLVPN with any certificate that is signed by a trusted Certificate Authority.
How severe is CVE-2021-24012?: CVE-2021-24012 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2021-24012 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-24012?: CVE-2021-24012 affects Fortinet Fortios. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-24012?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-24012 published?: CVE-2021-24012 was published on 2021-06-02 and last updated on 2026-06-17.

References

https://fortiguard.com/advisory/FG-IR-21-018

Affected products (1)

cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*

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