CVE-2026-111711 (GCVE-0-2026-111711)

Vulnerability from cvelistv5 – Published: 2026-10-16 17:40 – Updated: 2026-10-16 21:16
VLAI
Title
Netcore NR256CN through 1.5.140116 Pre-Auth Stack Overflow via Boa user_ok()
Summary
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.
Severity
9.3 (Critical)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-16 20:53 UTC
CWE
  • CWE-121 - Stack-based Buffer Overflow
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6373 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Netcore NR256CN Affected: 0 , ≤ 1.5.140116 (custom)
guessed Create a notification for this product.
Date Public
2026-10-16 00:00
Credits
Zhou Ao Yin Luxing Lu Fangzhou Liu Xin
Show details on NVD website
To clipboard 

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