Executive brief
The Netcore NR255-V router's Quality of Service (QoS) management feature fails to properly sanitize user input when processing QoS rule names. An attacker with administrative access can inject malicious script code that persists in the device's configuration and executes in the web interface whenever the rules are viewed or modified, potentially compromising administrative sessions and router security settings.
Technical details
This is a stored cross-site scripting (XSS) vulnerability in the QoS rule name handling of four CGI handlers: qos_xianz_add_cgi, qos_xianz_show_cgi, qos_filter_add_cgi, and qos_filter_show_cgi. The root cause is insufficient input sanitization before QoS rule names are processed via eval() statements, allowing attackers to inject arbitrary JavaScript code. An authenticated administrator can craft a malicious QoS rule name containing script code that persists in the router's configuration; the injected payload executes whenever the affected handlers process the stored data, affecting any user who subsequently views or manages QoS rules. The attack requires high privileges (administrator role), user interaction (visiting the affected web interface), and network access to the router's management interface. Patches or workarounds have not been explicitly noted in available advisories.
Affected products
- Netcore NR255-V 1.5.130703
Timeline
- 2026-09-04: disclosed
- 2026-09-15: advisory