---
id: CVE-2026-76866
title: >-
  Netcore NR255-V firmware version 1.5.130703 builds root-run command lines from
  unquoted user-supplied DDNS input in DDNSset_cgi.c and related ddns_Proc.c
  components, enabling os command argument injection
summary: >-
  Netcore NR255-V firmware version 1.5.130703 builds root-run command lines from
  unquoted user-supplied DDNS input in DDNSset_cgi.c and related ddns_Proc.c
  components, enabling os command argument injection. Attackers can exploit the
  unsan…
severity: high
cvss: 7.2
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-88
vendor: Netcore
product: NR255-V
affected:
  - NR255-V 1.5.130703
published: '2026-09-15'
updated: '2026-09-21'
sourceUpdated: '2026-09-21T18:17:10.530'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-76866'
references:
  - url: >-
      https://github.com/draw-ctf/netcore-router-public-refs/blob/main/2026.08.19-netcore-nr255v-ddns-argv-injection.md
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/netcore-nr255-v-1.5.130703-os-command-argument-injection-via-unquoted-ddns-parameters
    label: disclosure@vulncheck.com
tags:
  - nvd
  - cve.org
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-09-21T18:00:08.999146Z'
epss: 0.00572
epssPercentile: 0.44903
ingestedAt: '2026-09-15T22:45:31.289Z'
---

## Overview

Netcore NR255-V firmware version 1.5.130703 builds root-run command lines from unquoted user-supplied DDNS input in DDNSset_cgi.c and related ddns_Proc.c components, enabling os command argument injection. Attackers can exploit the unsanitized parameters to inject additional command arguments executed with root privileges.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.