SonicWall Email Security Unrestricted Upload of File Vulnerability
SonicWall Email Security contains an unrestricted upload of file with dangerous type vulnerability that allows a post-authenticated attacker to upload a file to the remote host. This vulnerability has known usage in a SonicWall Email Security exploit chain along with CVE-2021-20021 and CVE-2021-20023 to achieve privilege escalation.
- Vendor
- SonicWall
- Product
- SonicWall Email Security
- CVSS
- 7.2
- EPSS (exploit probability)
- 16.6%
- Status
- kevransomware use
- CISA patch-by (BOD 22-01)
- Added to KEV
Is CVE-2021-20022 being exploited?
Yes. CISA added CVE-2021-20022 to its Known Exploited Vulnerabilities catalog on . CISA only lists a CVE when it has reliable evidence of exploitation in the wild. CISA marks it as known to be used in ransomware campaigns.
FIRST's EPSS model puts the probability of exploitation activity in the next 30 days at 16.6% (scored October 14, 2026).
- CISA KEV[ LISTED ]
- ENISA EUVD (exploited)[ — ]
- CIRCL KEV[ — ]
Catalog snapshot 2026-10-21. Full cross-catalog view: /kev-comparison
What to do
CISA required actionApply updates per vendor instructions.
US federal civilian agencies must remediate by (14 days after listing) under BOD 22-01. Everyone else: that deadline is a sensible upper bound, not a target. Vendor guidance and the NVD record are linked under Source above.
Other SonicWall Email Security CVEs we track
| CVE / Vulnerability | Severity | CVSS | EPSS | Added to KEV |
|---|---|---|---|---|
| CVE-2021-20023 SonicWall Email Security Path Traversal Vulnerabilityransomware use | [ MEDIUM ] | 4.9 | 51.7% | |
| CVE-2021-20021 SonicWall Email Security Improper Privilege Management Vulnerabilityransomware use | [ CRITICAL ] | 9.8 | 88.8% |