External risk intelligence

Linksys E5600 Command Injection Vulnerability

CVE advisorySeverity: CRITICAL (CVSS 9.8)

CVE-2025-29228

The affected product is a Linksys E5600 wireless router. Routers of this type are frequently deployed as internet-facing edge devices. The vulnerability exists within the device's management interface, which is a common network-accessible surface in residential and small office environments.

Command Injection

Linksys E5600 Firmware

1.1.0.26

Halo Surface Signal: 4 out of 5 — likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

This advisory details a critical vulnerability found in Linksys E5600 firmware version 1.1.0.26. The issue allows for command injection, meaning an attacker could potentially execute arbitrary commands on the affected device. Given the nature of the affected technology, this could represent a significant security risk if exposed externally.

Device firmware allows attackers to run commands.
Routers are often internet-facing; exposure needs checking.
Confirm relevance and any potential exposure.

Attack Path

How an attacker could exploit the issue

An attacker could exploit this vulnerability by sending a specially crafted request over the network to a Linksys E5600 router. This request would target the runtime.macClone function, specifically manipulating the mc.ip parameter to inject malicious commands. If successful, this could allow the attacker to execute arbitrary code on the device.

No special access required.
Vulnerable function triggered via network request.
Allows arbitrary command execution.

Live Threat

Current exploitation, exposure, and threat context

When supported by the advisory, this vulnerability could allow an unauthenticated attacker to execute arbitrary commands on the affected device. This could impact the device's runtime behavior and potentially expose system data.

Device runtime and system data.
Via the `mc.ip` parameter in `runtime.macClone`.
Arbitrary command execution on the device.

Operational Fix

Recommended remediation, mitigation, and detection steps

The Linksys E5600 is a network device, likely managed by an infrastructure or network security team. The initial step involves identifying all instances of this device on the network, assessing their exposure (especially if internet-facing), and determining their business criticality to prioritize remediation efforts. Once accountable owners are identified, a maintenance window should be planned for applying any available fixes or implementing compensating controls.

Identify device instances and owners.
Verify external reachability and business impact.
Plan remediation in a maintenance window.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

Free EASM Trial See How Signal Works

Frequently asked questions

What is the Linksys E5600?

The Linksys E5600 is a dual-band Wi-Fi 6 router designed for residential and small office networking. It acts as a gateway device that manages local internet traffic, connects wireless devices to the network, and provides routing services. Users typically interact with its built-in web-based management interface to configure network settings, security, and device performance.

What does command injection mean for CVE-2025-29228?

This vulnerability is classified as CWE-77, or Improper Neutralization of Special Elements used in an OS Command. It means the router's software does not properly filter user input before processing it. By sending specific characters through the affected function, an attacker can trick the system into executing unauthorized, arbitrary system commands instead of simply processing a routine network configuration request.

How is this vulnerability triggered?

An attacker triggers the flaw by sending a specially crafted request to the router's internal runtime.macClone function via the mc.ip parameter. The bug is tied specifically to how this parameter handles input. Sending standard, legitimate configuration traffic or using the device for normal browsing does not trigger this malicious command execution.

Is my Linksys E5600 at risk?

Halo Surface Signal indicates that because this router is often used as an internet-facing edge device, it is more likely to be reached by unauthorized parties. If your router is configured with its management interface accessible from the internet rather than restricted to your local network, the risk of external exploitation is significantly higher.

How should I respond to this threat?

Start by auditing your network to locate all active Linksys E5600 devices and identify their primary administrators. Check if your device's management interface is accessible from the public internet and restrict access to local network connections only. Coordinate with your team to schedule a maintenance window to apply firmware updates or implement security controls to mitigate the risk.

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.