How severe is CVE-2021-20020?

CVE-2021-20020 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-20020 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20020?

CVE-2021-20020 affects Sonicwall Global Management System. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-20020?

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

When was CVE-2021-20020 published?

CVE-2021-20020 was published on 2021-04-10 and last updated on 2026-06-17.

CVE-2021-20020

CVE-2021-20020 is a critical-severity vulnerability in Sonicwall Global Management System with a CVSS 3.x base score of 9.8. 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-287.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
EPSS exploit prediction: 4% (89th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Sonicwall Global Management System
Published: 2021-04-10
Last modified: 2026-06-17

Description

A command execution vulnerability in SonicWall GMS 9.3 allows a remote unauthenticated attacker to locally escalate privilege to root.

Frequently asked questions

What is CVE-2021-20020?: A command execution vulnerability in SonicWall GMS 9.3 allows a remote unauthenticated attacker to locally escalate privilege to root.
How severe is CVE-2021-20020?: CVE-2021-20020 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-20020 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20020?: CVE-2021-20020 affects Sonicwall Global Management System. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-20020?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-20020 published?: CVE-2021-20020 was published on 2021-04-10 and last updated on 2026-06-17.

References

https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0009

Affected products (1)

cpe:2.3:a:sonicwall:global_management_system:9.3:*:*:*:*:*:*:*

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