CVE-2021-20038 on CISA KEV

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 affected SMA 200, 210, 400,

01What CISA says about this vulnerability

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 affected SMA 200, 210, 400, 410 and 500v appliances firmware 10.2.0.8-37sv, 10.2.1.1-19sv, 10.2.1.2-24sv and earlier versions.

02Required action — verbatim from CISA

Apply updates per vendor instructions.

03Notes & references

• psirt.global.sonicwall.com — https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0026
• github.com — https://github.com/jbaines-r7/badblood
• www.rapid7.com — https://www.rapid7.com/blog/post/2022/01/11/cve-2021-20038-42-sonicwall-sma-100-…

04SARA's analyst layer — why this matters

This vulnerability is currently on the CISA KEV list, which CISA only adds CVEs to when there is reliable evidence of active exploitation in the wild. For federal civilian agencies, BOD 22-01 requires remediation by the due date above. For everyone else, KEV is the strongest "patch immediately" signal you can get from public threat intel.

05Affected products (summary)

Vendor	Product	Versions
SonicWall	SonicWall SMA100	10.2.0.8-37sv and earlier, 10.2.1.1-19sv and earlier, 10.2.1.2-24sv and earlier

06Detection

Open the Sigma generator with a pre-filled prompt for this CVE to draft a starting detection:

Open in Sigma generator →