Actively exploited · Published Dec 8, 2021 · Assigned by sonicwall
CVE-2021-20038
Critical 9.8 Exploited Ransomware
In plain English
A critical-severity stack buffer overflow in SonicWall SMA100 from SonicWall. Attackers are actively exploiting it in the wild (listed by CISA on January 28, 2022). It has been used in ransomware campaigns. The chance it is exploited in the next 30 days is estimated at 99.9% (higher than 99.9% of all known vulnerabilities). Ready-made attack tooling exists: Nuclei, public proof-of-concept code. Apply updates per vendor instructions.
CISA guidance
Apply updates per vendor instructions.
Federal agencies must remediate by Feb 11, 2022.
Official description
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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| SonicWall | SonicWall SMA100 | 10.2.0.8-37sv and earlier10.2.1.1-19sv and earlier10.2.1.2-24sv and earlier |
Weakness: CWE-121 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
References
- https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0026 x_refsource_CONFIRM
- https://github.com/jbaines-r7/badblood x_refsource_MISC
- https://www.rapid7.com/blog/post/2022/01/11/cve-2021-20038-42-sonicwall-sma-100-multiple-vulnerabilities-fixed-2/ x_refsource_MISC
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-20038 government-resource