How severe is CVE-2021-20022?

CVE-2021-20022 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-20022 being actively exploited?

Yes. CVE-2021-20022 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-2021-20022?

CVE-2021-20022 primarily affects Sonicwall Email Security. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-20022?

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-2021-20022 have an EU (EUVD) identifier?

Yes. CVE-2021-20022 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-7485. It is also flagged as exploited in the EUVD (since 2021-11-03).

When was CVE-2021-20022 published?

CVE-2021-20022 was published on 2021-04-09 and last updated on 2026-06-17.

CVE-2021-20022

CVE-2021-20022 is a high-severity vulnerability in Sonicwall Email Security with a CVSS 3.x base score of 7.2. 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-434.

Key facts

Severity: High (CVSS 3.x base score 7.2)
CVSS v2: 7.5
EPSS exploit prediction: 17% (97th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2021-11-03)
EU (EUVD) id: EUVD-2021-7485
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2021-11-03)
Weakness: CWE-434
Affected product: Sonicwall Email Security
Published: 2021-04-09
Last modified: 2026-06-17

Description

SonicWall Email Security version 10.0.9.x contains a vulnerability that allows a post-authenticated attacker to upload an arbitrary file to the remote host.

Frequently asked questions

What is CVE-2021-20022?: SonicWall Email Security version 10.0.9.x contains a vulnerability that allows a post-authenticated attacker to upload an arbitrary file to the remote host.
How severe is CVE-2021-20022?: CVE-2021-20022 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-20022 being actively exploited?: Yes. CVE-2021-20022 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-2021-20022?: CVE-2021-20022 primarily affects Sonicwall Email Security. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-20022?: 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-2021-20022 have an EU (EUVD) identifier?: Yes. CVE-2021-20022 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-7485. It is also flagged as exploited in the EUVD (since 2021-11-03).
When was CVE-2021-20022 published?: CVE-2021-20022 was published on 2021-04-09 and last updated on 2026-06-17.

References

Affected products (11)

cpe:2.3:a:sonicwall:email_security:*:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:email_security_appliance_9000_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:email_security_appliance_3300_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:email_security_appliance_4300_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:email_security_appliance_8300_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:email_security_appliance_5000_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:email_security_appliance_7000_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:email_security_appliance_5050_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:email_security_appliance_7050_firmware:*:*:*:*:*:*:*:*
cpe:2.3:a:sonicwall:email_security_virtual_appliance:*:*:*:*:*:*:*:*
cpe:2.3:a:sonicwall:hosted_email_security:*:*:*:*:*:*:*:*

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