Wavlink WL-WN579X3-C adm.cgi sub_401AD4 クロスサイトスクリプティング

Successful exploitation of CVE-2026-3716 allows an attacker to inject arbitrary JavaScript code into the web interface of the Wavlink WL-WN579X3-C device. This can lead to a variety of malicious outcomes, including session hijacking, credential theft, and defacement of the device's administration pages. The remote nature of the vulnerability means an attacker does not need local access to the device, significantly expanding the potential attack surface. Given the device's role in network connectivity, a compromised device could also be used as a pivot point for further attacks within the network.

Small and medium-sized businesses (SMBs) and home users relying on Wavlink WL-WN579X3-C wireless adapters are at risk. Organizations with legacy network configurations or those using the device in environments with limited security controls are particularly vulnerable. Shared hosting environments where multiple users share the same device could also be impacted.

• linux / server: Monitor access logs for requests to /cgi-bin/adm.cgi containing unusual characters or patterns in the Hostname parameter. Use grep to search for suspicious input.

grep 'suspicious_pattern' /var/log/nginx/access.log

• generic web: Use curl to test the /cgi-bin/adm.cgi endpoint with various payloads in the Hostname parameter. Look for reflected input in the response.

curl 'http://<device_ip>/cgi-bin/adm.cgi?Hostname=<xss_payload>' -v

1. 2026-03-08Disclosure

   disclosure

2. 2026-03-08Patch

   patch

1. 予約済み2026-03-07
2. 公開日2026-03-08
3. 更新日2026-03-11
4. EPSS 更新日2026-03-23

The primary mitigation for CVE-2026-3716 is to upgrade the Wavlink WL-WN579X3-C firmware to version 20260226 or later. If an immediate upgrade is not possible due to compatibility issues or downtime concerns, consider implementing strict input validation on the Hostname parameter within the /cgi-bin/adm.cgi file. While not a complete solution, this can reduce the attack surface. Web application firewalls (WAFs) configured to detect and block XSS payloads targeting the /cgi-bin/adm.cgi endpoint can also provide a layer of defense. Monitor device logs for unusual activity, particularly requests containing suspicious characters in the Hostname parameter.