How severe is CVE-2021-20016?

CVE-2021-20016 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-2021-20016 being actively exploited?

Yes. CVE-2021-20016 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2021-11-03, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2021-20016?

CVE-2021-20016 primarily affects Sonicwall Sma 100 Firmware. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-20016?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2021-20016 have an EU (EUVD) identifier?

Yes. CVE-2021-20016 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-7479. It is also flagged as exploited in the EUVD (since 2021-11-03).

When was CVE-2021-20016 published?

CVE-2021-20016 was published on 2021-02-04 and last updated on 2026-08-12.

CVE-2021-20016

CVE-2021-20016 is a critical-severity vulnerability in Sonicwall Sma 100 Firmware with a CVSS 3.x base score of 9.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2021-11-03). The underlying weakness is classified as CWE-89.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 37% (98th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2021-11-03)
EU (EUVD) id: EUVD-2021-7479
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2021-11-03)
Weakness: CWE-89
Affected product: Sonicwall Sma 100 Firmware
Published: 2021-02-04
Last modified: 2026-08-12

Description

A SQL-Injection vulnerability in the SonicWall SSLVPN SMA100 product allows a remote unauthenticated attacker to perform SQL query to access username password and other session related information. This vulnerability impacts SMA100 build version 10.x.

Frequently asked questions

What is CVE-2021-20016?: A SQL-Injection vulnerability in the SonicWall SSLVPN SMA100 product allows a remote unauthenticated attacker to perform SQL query to access username password and other session related information. This vulnerability impacts SMA100 build version 10.x.
How severe is CVE-2021-20016?: CVE-2021-20016 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-2021-20016 being actively exploited?: Yes. CVE-2021-20016 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2021-11-03, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2021-20016?: CVE-2021-20016 primarily affects Sonicwall Sma 100 Firmware. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-20016?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2021-20016 have an EU (EUVD) identifier?: Yes. CVE-2021-20016 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-7479. It is also flagged as exploited in the EUVD (since 2021-11-03).
When was CVE-2021-20016 published?: CVE-2021-20016 was published on 2021-02-04 and last updated on 2026-08-12.

References

Affected products (6)

cpe:2.3:o:sonicwall:sma_100_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_200_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_210_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_400_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sma_410_firmware:-:*:*:*:*:*:*:*
cpe:2.3:a:sonicwall:sma_500v:-:*:*:*:*:*:*:*

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