How severe is CVE-2021-41016?

CVE-2021-41016 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-2021-41016 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-41016?

CVE-2021-41016 affects Fortinet Fortiextender Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-41016?

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-2021-41016 published?

CVE-2021-41016 was published on 2022-02-02 and last updated on 2026-06-17.

CVE-2021-41016

CVE-2021-41016 is a high-severity vulnerability in Fortinet Fortiextender Firmware 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: 9.0
EPSS exploit prediction: 1% (62nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-78
Affected product: Fortinet Fortiextender Firmware
Published: 2022-02-02
Last modified: 2026-06-17

Description

A improper neutralization of special elements used in a command ('command injection') in Fortinet FortiExtender version 7.0.1 and below, 4.2.3 and below, 4.1.7 and below allows an authenticated attacker to execute privileged shell commands via CLI commands including special characters

Frequently asked questions

What is CVE-2021-41016?: A improper neutralization of special elements used in a command ('command injection') in Fortinet FortiExtender version 7.0.1 and below, 4.2.3 and below, 4.1.7 and below allows an authenticated attacker to execute privileged shell commands via CLI commands including special characters
How severe is CVE-2021-41016?: CVE-2021-41016 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-2021-41016 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-41016?: CVE-2021-41016 affects Fortinet Fortiextender Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-41016?: 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-2021-41016 published?: CVE-2021-41016 was published on 2022-02-02 and last updated on 2026-06-17.

References

https://fortiguard.com/advisory/FG-IR-21-148

Affected products (1)

cpe:2.3:o:fortinet:fortiextender_firmware:*:*:*:*:*:*:*:*

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