CVE-2026-111711
CriticalCVSS 9.8Summary
Netcore NR256CN through 1.5.140116 contains a pre-authentication stack overflow vulnerability in the Boa web server's user_ok() function, which copies Basic-auth usernames with unbounded strcpy() calls into 64-byte stack buffers. Unauthenticated attackers can send a username longer than 63 bytes to any protected /router/*.cgi route to crash the main Boa process or potentially execute code.
Risk Assessment
An unauthenticated attacker can remotely crash the service or potentially execute arbitrary code, posing a serious threat to the device.
Recommendation
Update Netcore NR256CN software to a version later than 1.5.140116 if available, or apply mitigations.
Other vulnerabilities in Netcore NR256CN
See all- CVE-2026-111712Medium
Netcore NR256CN through 1.5.140116 contains an authentication bypass vulnerability that allows unauthenticated attackers to reach protected management CGI handlers by prefixing the URI with a public route. Attackers can request paths prefixed with l7_web_auth.cgi or an .ico route to invoke protected management handlers without credentials.
- CVE-2026-111710High
Netcore NR256CN through 1.5.140116 contains a NULL pointer dereference vulnerability in the Boa web server's user_auth() function that allows unauthenticated attackers to crash the server via a malformed Authorization header. Attackers can send a Basic Authorization value lacking a colon to protected routes like /router/get_user_type.cgi to kill the main Boa process and deny management interface access.
Original NVD description (English source)
Netcore NR256CN through 1.5.140116 contains a pre-authentication stack overflow vulnerability in the Boa web server's user_ok() function, which copies Basic-auth usernames with unbounded strcpy() calls into 64-byte stack buffers. Unauthenticated attackers can send a username longer than 63 bytes to any protected /router/*.cgi route to crash the main Boa process or potentially execute code.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS