How severe is CVE-2021-20049?

CVE-2021-20049 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-20049 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20049?

CVE-2021-20049 primarily affects Sonicwall Sma 100 Firmware. In total, 18 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-20049?

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-2021-20049 published?

CVE-2021-20049 was published on 2021-12-23 and last updated on 2026-06-17.

CVE-2021-20049

CVE-2021-20049 is a high-severity vulnerability in Sonicwall Sma 100 Firmware with a CVSS 3.x base score of 7.5. 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-203.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (68th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-203
Affected product: Sonicwall Sma 100 Firmware
Published: 2021-12-23
Last modified: 2026-06-17

Description

A vulnerability in SonicWall SMA100 password change API allows a remote unauthenticated attacker to perform SMA100 username enumeration based on the server responses. This vulnerability impacts 10.2.1.2-24sv, 10.2.0.8-37sv and earlier 10.x versions.

Frequently asked questions

What is CVE-2021-20049?: A vulnerability in SonicWall SMA100 password change API allows a remote unauthenticated attacker to perform SMA100 username enumeration based on the server responses. This vulnerability impacts 10.2.1.2-24sv, 10.2.0.8-37sv and earlier 10.x versions.
How severe is CVE-2021-20049?: CVE-2021-20049 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-20049 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20049?: CVE-2021-20049 primarily affects Sonicwall Sma 100 Firmware. In total, 18 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-20049?: 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-2021-20049 published?: CVE-2021-20049 was published on 2021-12-23 and last updated on 2026-06-17.

References

https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0030

Affected products (18)

cpe:2.3:o:sonicwall:sma_100_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_100_firmware:10.2.0.8-37sv:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_100_firmware:10.2.1.2-24sv:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_200_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_200_firmware:10.2.0.8-37sv:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_200_firmware:10.2.1.2-24sv:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_210_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_210_firmware:10.2.0.8-37sv:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_210_firmware:10.2.1.2-24sv:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_400_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_400_firmware:10.2.0.8-37sv:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_400_firmware:10.2.1.2-24sv:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_410_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_410_firmware:10.2.0.8-37sv:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_410_firmware:10.2.1.2-24sv:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_500v_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_500v_firmware:10.2.0.8-37sv:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_500v_firmware:10.2.1.2-24sv:*:*:*:*:*:*:*

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