CVE-2026-111711
CVE-2026-111711 · Netcore NR256CN through 1.5.140116 Pre-Auth Stack Overflow via Boa user_ok()
This page contains facts from public vulnerability sources. Check the original advisory before updating.
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.
CVSS 9.3 · Critical · EPSS 0.5%
- Published
- Updated
Affected products and versions
nr256cn
- Versions
- ≥ 0, ≤ 1.5.140116: Affected (custom)
No fix published
Original sources
- https://github.com/lukadqq/netcore-router-public-refs/blob/a44d562736b41c944223297e9144d2ad7fa2aff1/2026.10.15-netcore-nr256cn-basic-auth-stack-overflow.md
- https://www.vulncheck.com/advisories/netcore-nr256cn-through-1.5.140116-pre-auth-stack-overflow-via-boa-user-ok
- https://nvd.nist.gov/vuln/detail/CVE-2026-111711