CVE-2026-41926CWE-78

WDR201A WiFi Extender OS Command Injection via firewall.cgi

Critical · published May 4, 2026

CVSS v4.0
9.3
EPSS
2%
Percentile
79.5
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
9.3 · CRITICAL
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
EPSS
0.01903 · 79.5th percentile
Weakness
CWE-78 · Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Published
2026-05-04T19:17Z
EPSS history
Timeline
  • 04 MAY 19:17Z
    WDR201A WiFi Extender OS Command Injection via firewall.cgi
    cvelistv5