CVE-2026-4558: Linksys MR9600 SmartConnect.lua smartConnectConfigure os command injection

Vulnerability summary

CVE-2026-4558 is a high (CVSS 9.0) Command Injection vulnerability in linksys mr9600_firmware. EPSS estimates a 8.05% chance of exploitation in the next 30 days, higher than 94.7% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 22-03-2026
   PublishedVulnerability first disclosed.
2. 23-03-2026
   Last modifiedVulnerability information updated.

Description

A flaw has been found in Linksys MR9600 2.0.6.206937. Affected is the function smartConnectConfigure of the file SmartConnect.lua. Executing a manipulation of the argument configApSsid/configApPassphrase/srpLogin/srpPassword can lead to os command injection. The attack may be launched remotely. The exploit has been published and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

• CWE-77Improper Neutralization of Special Elements used in a Command ('Command Injection')The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component.
• CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.