How severe is CVE-2021-42758?

CVE-2021-42758 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-42758 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-42758?

CVE-2021-42758 primarily affects Fortinet Fortiwlc. In total, 15 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-42758?

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-2021-42758 published?

CVE-2021-42758 was published on 2021-12-08 and last updated on 2026-06-17.

CVE-2021-42758

CVE-2021-42758 is a high-severity vulnerability in Fortinet Fortiwlc with a CVSS 3.x base score of 8.8. 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-863.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 9.0
EPSS exploit prediction: 2% (79th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-863
Affected product: Fortinet Fortiwlc
Published: 2021-12-08
Last modified: 2026-06-17

Description

An improper access control vulnerability [CWE-284] in FortiWLC 8.6.1 and below may allow an authenticated and remote attacker with low privileges to execute any command as an admin user with full access rights via bypassing the GUI restrictions.

Frequently asked questions

What is CVE-2021-42758?: An improper access control vulnerability [CWE-284] in FortiWLC 8.6.1 and below may allow an authenticated and remote attacker with low privileges to execute any command as an admin user with full access rights via bypassing the GUI restrictions.
How severe is CVE-2021-42758?: CVE-2021-42758 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-42758 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-42758?: CVE-2021-42758 primarily affects Fortinet Fortiwlc. In total, 15 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-42758?: 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-2021-42758 published?: CVE-2021-42758 was published on 2021-12-08 and last updated on 2026-06-17.

References

https://fortiguard.com/advisory/FG-IR-21-200

Affected products (15)

cpe:2.3:a:fortinet:fortiwlc:*:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortiwlc:8.0.5:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortiwlc:8.0.6:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortiwlc:8.1.2:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortiwlc:8.1.3:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortiwlc:8.4.0:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortiwlc:8.4.1:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortiwlc:8.4.2:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortiwlc:8.4.4:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortiwlc:8.4.5:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortiwlc:8.4.6:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortiwlc:8.4.7:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortiwlc:8.4.8:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortiwlc:8.6.0:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortiwlc:8.6.1:*:*:*:*:*:*:*

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