CVE-2026-41926 PUBLISHED

WDR201A WiFi Extender OS Command Injection via firewall.cgi

Assigner: VulnCheck
Reserved: 22.04.2026 Published: 04.05.2026 Updated: 04.05.2026

WDR201A WiFi Extender (HW V2.1, FW LFMZX28040922V1.02) contains an OS command injection vulnerability in the firewall.cgi binary across five request handlers that apply insufficient input validation. Attackers can inject arbitrary shell commands through vulnerable parameters like websURLFilter, websHostFilter, portForward, singlePortForward, and ipportFilter using subshell syntax or unfiltered parameters, with payloads persisting in NVRAM and re-executing on every subsequent firewall.cgi request.

Metrics

CVSS 4.0

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CVSS Score: 9.3

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	High	Confidentiality	None
Attack Complexity	Low	Integrity	High	Integrity	None
Attack Requirements	None	Availability	High	Availability	None
Privileges Required	None
User Interaction	None

CVSS 4.0

Product Status

Vendor	Shenzhen Yipu Commercial and Trading Co., Ltd
Product	WDR201A WiFi Extender
Versions	Default: unaffected affected from 0 to 1.02 (incl.)

Credits

Matteo Strada finder

References

Problem Types

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') (CWE-78) CWE