CVE-2026-76866

Deferred Deferred - Pending Action

Netcore NR255-V Firmware OS Command Injection

Publication date: 2026-09-15

Last updated on: 2026-09-21

Assigner: VulnCheck

Description

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.

CVSS Scores

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Meta Information

Published

2026-09-15

Last Modified

2026-09-21

Generated

2026-10-06

AI Q&A

2026-09-16

EPSS Evaluated

2026-10-04

NVD

CVE-2026-76866

EUVD

EUVD-2026-80038

Affected Vendors & Products

Vendor	Product	Version / Range
netcore	nr255-v	1.5.130703

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-88	The product constructs a string for a command to be executed by a separate component in another control sphere, but it does not properly delimit the intended arguments, options, or switches within that command string.

Attack-Flow Graph

Executive Summary

This vulnerability is an OS command injection flaw in Netcore NR255-V firmware version 1.5.130703. It occurs because user-supplied DDNS input is used to build root-run command lines without proper quoting in DDNSset_cgi.c and ddns_Proc.c components. Attackers can inject additional command arguments that execute with root privileges due to unsanitized parameters.

Detection Guidance

Detecting this vulnerability requires checking for unsanitized DDNS input handling in Netcore NR255-V firmware. Inspect network traffic for malformed DDNS requests or unusual command injection patterns. Review logs for root-run command execution traces. No specific commands are provided in the context.

Impact Analysis

An attacker could exploit this to execute arbitrary commands on the device with root privileges. This may allow full system compromise, unauthorized access, data theft, or disruption of services. The impact depends on the device's role in the network and the commands executed.

Compliance Impact

This vulnerability could lead to unauthorized access or data breaches, violating GDPR's integrity and confidentiality requirements or HIPAA's safeguards for protected health information. Non-compliance may result in legal penalties, fines, or reputational damage depending on the affected data and jurisdiction.

Mitigation Strategies

Immediately update the Netcore NR255-V firmware to the latest patched version. Disable or restrict DDNS input handling if not required. Implement input validation and sanitization for all DDNS parameters. Monitor for suspicious command execution activities.

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