How severe is CVE-2021-36169?

CVE-2021-36169 has a CVSS 3.x base score of 4.2, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2021-36169 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (16th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-36169?

CVE-2021-36169 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-2021-36169?

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

When was CVE-2021-36169 published?

CVE-2021-36169 was published on 2021-12-13 and last updated on 2026-06-17.

CVE-2021-36169

CVE-2021-36169 is a medium-severity vulnerability in Fortinet Fortios with a CVSS 3.x base score of 4.2. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 4.2)
CVSS v2: 6.6
EPSS exploit prediction: 0% (16th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Fortinet Fortios
Published: 2021-12-13
Last modified: 2026-06-17

Description

A Hidden Functionality in Fortinet FortiOS 7.x before 7.0.1, FortiOS 6.4.x before 6.4.7 allows attacker to Execute unauthorized code or commands via specific hex read/write operations.

Frequently asked questions

What is CVE-2021-36169?: A Hidden Functionality in Fortinet FortiOS 7.x before 7.0.1, FortiOS 6.4.x before 6.4.7 allows attacker to Execute unauthorized code or commands via specific hex read/write operations.
How severe is CVE-2021-36169?: CVE-2021-36169 has a CVSS 3.x base score of 4.2, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2021-36169 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (16th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-36169?: CVE-2021-36169 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-2021-36169?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-36169 published?: CVE-2021-36169 was published on 2021-12-13 and last updated on 2026-06-17.

References

https://fortiguard.com/advisory/FG-IR-21-091

Affected products (2)

cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
cpe:2.3:o:fortinet:fortios:7.0.0:*:*:*:*:*:*:*

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