Buffer overflow in Sonicwall Sma_200

CVE-2021-20038

A Stack-based buffer overflow vulnerability in SMA100 Apache httpd server's mod_cgi module environment variables allows a remote unauthenticated attacker to potentially execute code as a 'nobody' user in the appliance. This vulnerability a…

Vulnerability class: Buffer Overflow

EPSS: 0.999 (100.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on . CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: .

Required action: Apply updates per vendor instructions.

Known ransomware campaign use: yes.

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-20038?
CVE-2021-20038 is a critical-severity vulnerability in Sonicwall Sma_200, classified under Stack-based Buffer Overflow. CVSS score: 9.8/10. Published 2021-12-08.
How severe is CVE-2021-20038?
Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2021-20038 known to be exploited?
Yes. CVE-2021-20038 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-01-28), indicating it is being actively exploited. 29 public proof-of-concept repositories are indexed.