How severe is CVE-2021-26106?

CVE-2021-26106 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-26106 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-26106?

CVE-2021-26106 primarily affects Fortinet Fortiap. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-26106?

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-2021-26106 published?

CVE-2021-26106 was published on 2021-07-09 and last updated on 2026-06-17.

CVE-2021-26106

CVE-2021-26106 is a high-severity vulnerability in Fortinet Fortiap with a CVSS 3.x base score of 7.8. 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-78.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 4.6
EPSS exploit prediction: 0% (21st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-78
Affected product: Fortinet Fortiap
Published: 2021-07-09
Last modified: 2026-06-17

Description

An improper neutralization of special elements used in an OS Command vulnerability in FortiAP's console 6.4.1 through 6.4.5 and 6.2.4 through 6.2.5 may allow an authenticated attacker to execute unauthorized commands by running the kdbg CLI command with specifically crafted arguments.

Frequently asked questions

What is CVE-2021-26106?: An improper neutralization of special elements used in an OS Command vulnerability in FortiAP's console 6.4.1 through 6.4.5 and 6.2.4 through 6.2.5 may allow an authenticated attacker to execute unauthorized commands by running the kdbg CLI command with specifically crafted arguments.
How severe is CVE-2021-26106?: CVE-2021-26106 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-26106 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-26106?: CVE-2021-26106 primarily affects Fortinet Fortiap. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-26106?: 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-2021-26106 published?: CVE-2021-26106 was published on 2021-07-09 and last updated on 2026-06-17.

References

https://fortiguard.com/advisory/FG-IR-20-210

Affected products (3)

cpe:2.3:a:fortinet:fortiap:*:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortiap-s:*:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortiap-w2:*:*:*:*:*:*:*:*

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