How severe is CVE-2020-12812?

CVE-2020-12812 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-12812 being actively exploited?

Yes. CVE-2020-12812 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2021-11-03, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2020-12812?

CVE-2020-12812 primarily affects Fortinet Fortios. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-12812?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2020-12812 have an EU (EUVD) identifier?

Yes. CVE-2020-12812 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2020-5095. It is also flagged as exploited in the EUVD (since 2021-11-03).

When was CVE-2020-12812 published?

CVE-2020-12812 was published on 2020-07-24 and last updated on 2026-08-12.

CVE-2020-12812

CVE-2020-12812 is a critical-severity vulnerability in Fortinet Fortios with a CVSS 3.x base score of 9.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2021-11-03). The underlying weakness is classified as CWE-178.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 49% (99th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2021-11-03)
EU (EUVD) id: EUVD-2020-5095
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2021-11-03)
Weakness: CWE-178
Affected product: Fortinet Fortios
Published: 2020-07-24
Last modified: 2026-08-12

Description

An improper authentication vulnerability in SSL VPN in FortiOS 6.4.0, 6.2.0 to 6.2.3, 6.0.9 and below may result in a user being able to log in successfully without being prompted for the second factor of authentication (FortiToken) if they changed the case of their username.

Frequently asked questions

What is CVE-2020-12812?: An improper authentication vulnerability in SSL VPN in FortiOS 6.4.0, 6.2.0 to 6.2.3, 6.0.9 and below may result in a user being able to log in successfully without being prompted for the second factor of authentication (FortiToken) if they changed the case of their username.
How severe is CVE-2020-12812?: CVE-2020-12812 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-12812 being actively exploited?: Yes. CVE-2020-12812 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2021-11-03, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2020-12812?: CVE-2020-12812 primarily affects Fortinet Fortios. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-12812?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2020-12812 have an EU (EUVD) identifier?: Yes. CVE-2020-12812 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2020-5095. It is also flagged as exploited in the EUVD (since 2021-11-03).
When was CVE-2020-12812 published?: CVE-2020-12812 was published on 2020-07-24 and last updated on 2026-08-12.

References

Affected products (2)

cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
cpe:2.3:o:fortinet:fortios:6.4.0:*:*:*:*:*:*:*

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