CVE-2026-1448: D-Link DIR-615 Firmware RCE Vulnerability

CVE-2026-1448 Overview

A critical OS command injection vulnerability has been identified in D-Link DIR-615 routers running firmware versions up to 4.10. This vulnerability affects the Web Management Interface, specifically in the /wiz_policy_3_machine.php file. Remote attackers with administrative privileges can exploit this vulnerability by manipulating the ipaddr argument to inject arbitrary operating system commands, potentially gaining complete control over the affected device.

Critical Impact

Remote authenticated attackers can execute arbitrary OS commands on affected D-Link DIR-615 routers, potentially leading to complete device compromise, network infiltration, and use of the device in botnet attacks. This vulnerability affects end-of-life products with no vendor support.

Affected Products

• D-Link DIR-615 Firmware versions up to 4.10
• D-Link DIR-615 Hardware (all variants running affected firmware)

Discovery Timeline

• 2026-01-27 - CVE-2026-1448 published to NVD
• 2026-01-28 - Last updated in NVD database

Technical Details for CVE-2026-1448

Vulnerability Analysis

This command injection vulnerability (CWE-77, CWE-78) exists within the Web Management Interface of D-Link DIR-615 routers. The vulnerable component is located in /wiz_policy_3_machine.php, which fails to properly sanitize the ipaddr parameter before passing it to system-level commands. An authenticated attacker with access to the web management interface can craft malicious input that escapes the intended command context and executes arbitrary OS commands with the privileges of the web server process—typically root on embedded devices.

The vulnerability requires network access and high privileges (administrative authentication), but once these conditions are met, exploitation is straightforward with no user interaction required. Successful exploitation results in complete compromise of confidentiality, integrity, and availability of the affected device.

Root Cause

The root cause is improper input validation and lack of sanitization on the ipaddr parameter in the /wiz_policy_3_machine.php script. The PHP script likely passes user-supplied input directly to shell commands (such as ping, traceroute, or similar network utilities) without properly escaping or validating the input. This allows attackers to inject shell metacharacters and additional commands that will be executed by the underlying operating system.

Attack Vector

The attack is conducted remotely over the network through the device's web management interface. An attacker must first authenticate to the router's administrative interface (either through valid credentials, default credentials, or credential compromise). Once authenticated, the attacker can navigate to or directly POST to the vulnerable endpoint and inject OS commands via the ipaddr parameter. Common injection techniques include command chaining using shell operators such as ;, |, &&, or backticks to append malicious commands.

The vulnerability mechanism involves improper handling of user input in the web management interface. When a user submits a value for the ipaddr parameter, the application passes this value to an underlying system command without adequate sanitization. An attacker can exploit this by including shell metacharacters followed by arbitrary commands. For example, instead of a valid IP address, an attacker could submit a value containing command separators that cause additional commands to execute on the system. For detailed technical information, see the Notion Security Document and VulDB #342880.

Detection Methods for CVE-2026-1448

Indicators of Compromise

• Unusual HTTP POST requests to /wiz_policy_3_machine.php containing shell metacharacters (;, |, &&, `, $()) in the ipaddr parameter
• Unexpected outbound network connections from the router to unknown external IP addresses
• Presence of unauthorized files or scripts in the router's filesystem
• Unexpected processes running on the device or abnormal CPU/memory utilization

Detection Strategies

• Implement network intrusion detection rules to monitor for HTTP requests containing command injection patterns targeting /wiz_policy_3_machine.php
• Deploy web application firewall (WAF) rules to inspect and block requests with shell metacharacters in form parameters
• Monitor router logs for repeated authentication attempts or unusual administrative activity
• Use network flow analysis to detect anomalous traffic patterns from router devices

Monitoring Recommendations

• Enable and centrally collect web management interface access logs from D-Link routers
• Set up alerts for any access to /wiz_policy_3_machine.php with parameters containing non-IP address characters
• Monitor for unexpected DNS queries or network connections originating from router management interfaces
• Implement baseline monitoring for router behavior and alert on deviations

How to Mitigate CVE-2026-1448

Immediate Actions Required

• Replace affected D-Link DIR-615 devices with currently supported router models, as this product has reached end-of-life
• If immediate replacement is not possible, disable remote management access and restrict web interface access to trusted internal networks only
• Change default administrative credentials to strong, unique passwords
• Implement network segmentation to isolate legacy devices from critical network assets
• Consider using a firewall to block external access to the router's management interface

Patch Information

D-Link has declared the DIR-615 as end-of-life, and no official patch will be released for this vulnerability. The vendor recommends replacing the affected device with a currently supported model. For more information, visit the D-Link Security Homepage.

Workarounds

• Disable the web management interface if not required for device administration
• Configure access control lists (ACLs) to restrict management interface access to specific trusted IP addresses only
• Place the router behind a firewall that blocks access to the management interface from untrusted networks
• Monitor and log all access attempts to the management interface for forensic purposes
• Consider using third-party firmware (such as DD-WRT or OpenWrt if supported) as an alternative, though this carries its own risks

# Network-level mitigation: Block external access to router management
# Example iptables rule to restrict management access to internal network only
iptables -A INPUT -p tcp --dport 80 -s 192.168.1.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP