CVE-2026-1970: Edimax BR-6258n Open Redirect Vulnerability

CVE-2026-1970 Overview

An open redirect vulnerability has been discovered in Edimax BR-6258n routers up to firmware version 1.18. This flaw affects the function formStaDrvSetup within the file /goform/formStaDrvSetup. By manipulating the submit-url argument, a remote attacker can redirect users to arbitrary external URLs. The exploit has been publicly disclosed, and the vendor has confirmed that the affected product is end-of-life, meaning no patches will be released. This vulnerability poses a significant risk for phishing attacks and credential theft scenarios targeting users of these legacy network devices.

Critical Impact

End-of-life network device vulnerable to open redirect attacks, enabling phishing campaigns and credential theft with no vendor patches available.

Affected Products

• Edimax BR-6258n firmware version 1.18 and earlier
• End-of-life consumer routers still in active use
• Network environments using legacy Edimax hardware

Discovery Timeline

• 2026-02-05 - CVE CVE-2026-1970 published to NVD
• 2026-02-05 - Last updated in NVD database

Technical Details for CVE-2026-1970

Vulnerability Analysis

This vulnerability is classified as CWE-601 (URL Redirection to Untrusted Site, also known as Open Redirect). The flaw exists in the web management interface of the Edimax BR-6258n router, specifically within the formStaDrvSetup handler. The router fails to properly validate the submit-url parameter before using it as a redirect destination, allowing attackers to craft malicious URLs that redirect authenticated users to attacker-controlled websites.

The attack can be initiated remotely over the network, requiring low privileges and some user interaction to succeed. While the direct impact on confidentiality is minimal, the vulnerability enables integrity violations through phishing attacks where users believe they are interacting with the legitimate router interface.

Root Cause

The root cause is insufficient input validation in the formStaDrvSetup function. The submit-url parameter is accepted and used directly for URL redirection without verifying that the destination is within the trusted domain or a relative path. This allows external, untrusted URLs to be injected, breaking the expected navigation flow within the router's web interface.

Attack Vector

An attacker can exploit this vulnerability by crafting a malicious link containing the router's web interface URL with a manipulated submit-url parameter pointing to an attacker-controlled site. When an authenticated user clicks this link, they are redirected to the malicious site after interacting with the legitimate router interface.

The attack flow typically involves:

1. Attacker identifies a target network using the vulnerable Edimax BR-6258n router
2. Attacker crafts a URL targeting /goform/formStaDrvSetup with a malicious submit-url parameter
3. The link is delivered to victims via phishing emails or malicious websites
4. When users click the link and authenticate, they are redirected to the attacker's site
5. The attacker can then harvest credentials or serve malware from the redirect destination

Technical details about this vulnerability can be found in the Notion Vulnerability Report and the VulDB entry #344492.

Detection Methods for CVE-2026-1970

Indicators of Compromise

• HTTP requests to /goform/formStaDrvSetup containing external URLs in the submit-url parameter
• Unusual redirect patterns from the router's web interface to external domains
• User reports of being redirected to unexpected websites after router management tasks
• Network traffic showing connections from router management sessions to unknown external hosts

Detection Strategies

• Monitor web server logs on network devices for requests to /goform/formStaDrvSetup with suspicious submit-url values
• Implement network monitoring to detect redirect responses (HTTP 302/301) from router IP addresses pointing to external domains
• Deploy URL filtering rules to alert on crafted links targeting the vulnerable endpoint
• Use intrusion detection signatures to identify exploitation attempts targeting the submit-url parameter

Monitoring Recommendations

• Configure alerts for HTTP requests to Edimax router interfaces containing the formStaDrvSetup path
• Implement web proxy logging to capture and analyze router management traffic patterns
• Establish baseline behavior for router web interface access and alert on anomalies
• Monitor DNS queries from the network segment where the router resides for unusual external domain lookups

How to Mitigate CVE-2026-1970

Immediate Actions Required

• Identify all Edimax BR-6258n devices in your network inventory and prioritize replacement planning
• Restrict access to the router's web management interface to trusted internal IP addresses only
• Implement network segmentation to isolate legacy devices from critical network segments
• Educate users about phishing risks associated with router management links
• Consider disabling remote web management if not strictly required

Patch Information

The vendor (Edimax) has confirmed that the affected BR-6258n product is end-of-life and no security patches will be released. Edimax has stated they "will issue a consolidated Security Advisory on their official support website." Organizations using this hardware should plan for device replacement as the primary mitigation strategy.

For additional details, refer to VulDB #344492 and VulDB Submission #742734.

Workarounds

• Restrict web interface access using firewall rules to allow only trusted administrator IP addresses
• Deploy a reverse proxy with URL validation in front of the router's web interface
• Disable the web management interface entirely and use alternative configuration methods if available
• Implement network access controls to prevent unauthorized access to the router management subnet
• Replace end-of-life devices with supported hardware that receives security updates

# Configuration example
# Example iptables rules to restrict access to router web interface
# Replace 192.168.1.1 with your router's IP address
# Replace 10.0.0.100 with trusted administrator IP

# Drop all external access to router web interface
iptables -A FORWARD -d 192.168.1.1 -p tcp --dport 80 -j DROP

# Allow only trusted admin IP to access router management
iptables -I FORWARD -s 10.0.0.100 -d 192.168.1.1 -p tcp --dport 80 -j ACCEPT

# Log blocked access attempts for monitoring
iptables -A FORWARD -d 192.168.1.1 -p tcp --dport 80 -j LOG --log-prefix "EDIMAX_BLOCKED: "