Known exploited · SonicWall
CVE-2021-20038: SonicWall SMA 100 Appliances Stack-Based Buffer Overflow Vulnerability
What it is
SonicWall SMA 100 devies are vulnerable to an unauthenticated stack-based buffer overflow vulnerability where exploitation can result in code execution.
- Vendor
- SonicWall
- Product
- SMA 100 Appliances
- Added to KEV
- January 28, 2022
- CISA due date
- February 11, 2022
- Ransomware use
- Known
What CISA requires
Apply updates per vendor instructions.
Forensic triage
No
What to do now
- Find every instance of SMA 100 Appliances you run, including the forgotten ones, and check its version against the vendor advisory.
- Apply the vendor's fix or mitigation, before February 11, 2022 if you are bound by CISA's deadline, sooner if it faces the internet.
- Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.
References
H2 Security
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Start freeSource: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.