How severe is CVE-2021-22124?

CVE-2021-22124 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-22124 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-22124?

CVE-2021-22124 primarily affects Fortinet Fortiauthenticator. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-22124?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-22124 published?

CVE-2021-22124 was published on 2021-08-04 and last updated on 2026-06-17.

CVE-2021-22124

CVE-2021-22124 is a high-severity vulnerability in Fortinet Fortiauthenticator with a CVSS 3.x base score of 7.5. 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-400.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 7.8
EPSS exploit prediction: 1% (59th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-400
Affected product: Fortinet Fortiauthenticator
Published: 2021-08-04
Last modified: 2026-06-17

Description

An uncontrolled resource consumption (denial of service) vulnerability in the login modules of FortiSandbox 3.2.0 through 3.2.2, 3.1.0 through 3.1.4, and 3.0.0 through 3.0.6; and FortiAuthenticator before 6.0.6 may allow an unauthenticated attacker to bring the device into an unresponsive state via specifically-crafted long request parameters.

Frequently asked questions

What is CVE-2021-22124?: An uncontrolled resource consumption (denial of service) vulnerability in the login modules of FortiSandbox 3.2.0 through 3.2.2, 3.1.0 through 3.1.4, and 3.0.0 through 3.0.6; and FortiAuthenticator before 6.0.6 may allow an unauthenticated attacker to bring the device into an unresponsive state via specifically-crafted long request parameters.
How severe is CVE-2021-22124?: CVE-2021-22124 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-22124 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-22124?: CVE-2021-22124 primarily affects Fortinet Fortiauthenticator. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-22124?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-22124 published?: CVE-2021-22124 was published on 2021-08-04 and last updated on 2026-06-17.

References

https://fortiguard.com/advisory/FG-IR-20-170

Affected products (2)

cpe:2.3:a:fortinet:fortiauthenticator:*:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortisandbox:*:*:*:*:*:*:*:*

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