CVE-2026-111711

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 v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
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

Configurations

No configuration.

History

16 Oct 2026, 18:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-16 18:17

Updated : 2026-10-16 22:17

NVD link : CVE-2026-111711

Mitre link : CVE-2026-111711

CVE.ORG link : CVE-2026-111711

JSON object : View

Products Affected

No product.

CWE

CWE-121

Stack-based Buffer Overflow

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