Critical severity9.8NVD Advisory· Published Oct 16, 2026· Updated Oct 16, 2026

CVE-2026-111711

Description

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.

Affected products

Netcore/NR256CNllm-create
Range: <=1.5.140116

Patches

Vulnerability mechanics

References

github.com/lukadqq/netcore-router-public-refs/blob/a44d562736b41c944223297e9144d2ad7fa2aff1/2026.10.15-netcore-nr256cn-basic-auth-stack-overflow.mdnvd
www.vulncheck.com/advisories/netcore-nr256cn-through-1.5.140116-pre-auth-stack-overflow-via-boa-user-oknvd

News mentions

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ransomware	0.000