CVE intelligence and bounded remediation

CVE-2021-20041 — Sonicwall Sma 200 Firmware security vulnerability

High CVSS 7.8

An unauthenticated and remote adversary can consume all of the device's CPU due to crafted HTTP requests sent to SMA100 /fileshare/sonicfiles/sonicfiles resulting in a loop with unreachable exit condition. This vulnerability affected SMA 200, 210, 400, 410 and 500v appliances.

Severity
High
CVSS
7.8 (2.0)
Published
2021-12-08
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-835

Affected products

  • sonicwall / sma_200_firmware / 9.0.0.11-31sv
  • sonicwall / sma_200_firmware / 10.2.0.8-37sv
  • sonicwall / sma_200_firmware / 10.2.1.1-19sv
  • sonicwall / sma_210_firmware / 9.0.0.11-31sv
  • sonicwall / sma_210_firmware / 10.2.0.8-37sv
  • sonicwall / sma_210_firmware / 10.2.1.1-19sv

Showing 6 representative product identities from 15 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

Matched remediation archetype

General vulnerability remediation

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Confirm the affected component, deployment paths, reachable interfaces, and enabled features from inventories and configuration, without probing production destructively.
  • Compare the advisory's affected conditions with the repository lockfiles, build manifests, artifacts, and runtime inventory.
  • Identify data sensitivity, trust boundaries, and privilege level for every confirmed affected deployment.

Remediate safely

  • Apply a vendor-supported fix or remove the affected component or feature; record the selected change and its source in the repository.
  • Update direct and transitive dependency locks, generated artifacts, deployment manifests, and asset inventories together.
  • Add a regression test for the documented unsafe condition using inert inputs and preserve rollback instructions.

Authoritative sources

Complete CVE record and remediation plan

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