CVE-2026-6373 Overview
CVE-2026-6373 is an information disclosure vulnerability in Zyxel Networks WAH7601 devices. The flaw allows an unauthenticated attacker on an adjacent network to perform web application fingerprinting against the device. The issue is tracked under CWE-497: Exposure of Sensitive System Information to an Unauthorized Control Sphere.
The vulnerability affects WAH7601 firmware through version 20072026. Successful exploitation exposes internal system details that attackers can use to identify software versions, plan targeted follow-on attacks, and prepare exploitation of additional weaknesses.
Critical Impact
An adjacent-network attacker can enumerate sensitive system information from the WAH7601 web interface without authentication, enabling reconnaissance for further attacks.
Affected Products
- Zyxel Networks WAH7601 through firmware version 20072026
Discovery Timeline
- 2026-08-10 - CVE-2026-6373 published to NVD
- 2026-08-10 - Last updated in NVD database
Technical Details for CVE-2026-6373
Vulnerability Analysis
CVE-2026-6373 is an information disclosure issue affecting the WAH7601 mobile router. The device exposes sensitive system information through its web application, which allows unauthenticated clients on the adjacent network to fingerprint the underlying software stack.
Web application fingerprinting reveals characteristics such as server software, framework versions, exposed endpoints, and configuration details. Attackers correlate this data with known vulnerabilities to plan targeted exploitation. The exposure is limited to confidentiality; the flaw does not directly affect integrity or availability of the device.
An attacker must be on the same wireless or physical network segment as the device. No credentials or user interaction are required, which lowers the barrier for opportunistic reconnaissance during network compromise scenarios. The EPSS forecast places the probability of observed exploitation activity at the lower end of the range.
Root Cause
The root cause is classified under CWE-497, which describes the exposure of sensitive system information to actors outside the intended control sphere. The WAH7601 web interface returns identifying data in HTTP responses, headers, or error messages without filtering the output for unauthenticated clients.
Attack Vector
The attack requires network adjacency to the WAH7601. An attacker sends crafted HTTP requests to the device's web management interface and inspects responses for version banners, framework signatures, and other implementation-specific artifacts. The resulting fingerprint informs subsequent attacks against the device or connected clients.
Specific technical details of the exposed endpoints are described in the Siber Güvenlik Advisory TR-26-0799.
Detection Methods for CVE-2026-6373
Indicators of Compromise
- Unusual volumes of HTTP GET requests to the WAH7601 web management interface from adjacent-network clients
- Repeated requests targeting version pages, static assets, or error-triggering URLs consistent with fingerprinting tools
- Responses returning distinctive software banners or framework signatures to unauthenticated clients
Detection Strategies
- Monitor wireless and LAN segments for HTTP scanning patterns directed at the router's management IP
- Inspect web server access logs on the WAH7601 for automated user-agent strings associated with tools such as whatweb, wappalyzer, or nmap HTTP scripts
- Correlate reconnaissance activity with subsequent authentication attempts or exploitation traffic against the same host
Monitoring Recommendations
- Enable logging on network infrastructure that observes traffic to and from the WAH7601 web interface
- Alert on unauthenticated HTTP requests originating from unexpected client MAC addresses on management interfaces
- Review firmware version and management interface exposure during routine device audits
How to Mitigate CVE-2026-6373
Immediate Actions Required
- Restrict access to the WAH7601 web management interface to trusted administrative hosts only
- Disable remote management on untrusted network segments and guest wireless networks
- Inventory all WAH7601 deployments and confirm firmware version against 20072026
- Monitor vendor channels for a firmware update that addresses CVE-2026-6373
Patch Information
At the time of publication, no fixed firmware version has been published in the referenced advisories. Consult the Siber Güvenlik Advisory TR-26-0799 and Zyxel security notifications for updated patch availability.
Workarounds
- Segment the WAH7601 management network from user and guest traffic using VLANs or dedicated SSIDs
- Apply firewall rules that limit inbound connections to the device's web interface to a defined administrative range
- Change default credentials and disable unused management services to reduce the attack surface exposed by fingerprinting
# Example firewall rule restricting WAH7601 management access to a single admin host
iptables -A INPUT -p tcp --dport 80 -s 192.0.2.10 -d <WAH7601_IP> -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -d <WAH7601_IP> -j DROP
iptables -A INPUT -p tcp --dport 443 -s 192.0.2.10 -d <WAH7601_IP> -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -d <WAH7601_IP> -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
