How severe is CVE-2021-20045?

CVE-2021-20045 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-2021-20045 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 25% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20045?

CVE-2021-20045 primarily affects Sonicwall Sma 200 Firmware. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-20045?

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-2021-20045 published?

CVE-2021-20045 was published on 2021-12-08 and last updated on 2026-06-17.

CVE-2021-20045

CVE-2021-20045 is a critical-severity vulnerability in Sonicwall Sma 200 Firmware with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 25% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-120.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 25% (98th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-120
Affected product: Sonicwall Sma 200 Firmware
Published: 2021-12-08
Last modified: 2026-06-17

Description

A buffer overflow vulnerability in SMA100 sonicfiles RAC_COPY_TO (RacNumber 36) method allows a remote unauthenticated attacker to potentially execute code as the 'nobody' user in the appliance. This vulnerability affected SMA 200, 210, 400, 410 and 500v appliances.

Frequently asked questions

What is CVE-2021-20045?: A buffer overflow vulnerability in SMA100 sonicfiles RAC_COPY_TO (RacNumber 36) method allows a remote unauthenticated attacker to potentially execute code as the 'nobody' user in the appliance. This vulnerability affected SMA 200, 210, 400, 410 and 500v appliances.
How severe is CVE-2021-20045?: CVE-2021-20045 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-2021-20045 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 25% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20045?: CVE-2021-20045 primarily affects Sonicwall Sma 200 Firmware. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-20045?: 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-2021-20045 published?: CVE-2021-20045 was published on 2021-12-08 and last updated on 2026-06-17.

References

https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0026

Affected products (10)

cpe:2.3:o:sonicwall:sma_200_firmware:10.2.0.8-37sv:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_200_firmware:10.2.1.1-19sv:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_210_firmware:10.2.0.8-37sv:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_210_firmware:10.2.1.1-19sv:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_410_firmware:10.2.0.8-37sv:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_410_firmware:10.2.1.1-19sv:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_400_firmware:10.2.0.8-37sv:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_400_firmware:10.2.1.1-19sv:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_500v_firmware:10.2.0.8-37sv:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_500v_firmware:10.2.1.1-19sv:*:*:*:*:*:*:*

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