CVE-2026-10831: Improper Authorization of Break Signal Commands in Devices
A denial-of-service vulnerability exists in NPort devices because of improper access control on the command port. The command interface does not properly validate whether a sender is associated with a valid data port session before accepting break signal commands. A remote attacker with network access can send crafted requests to disrupt serial communication for an active user session.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Configuration
If remote access to the command port is not required, disable it. Otherwise restrict command-port access to only trusted management IPs/networks (use device configuration to limit management interfaces to administrative hosts).
NPort command interface remote_access = disabled or restricted to trusted IPs - Compensating control
Implement network-level controls to prevent untrusted hosts from sending commands to the NPort command port: place devices on a management VLAN, enforce firewall/ACL rules to block the command port from untrusted networks, and allow only specific IP addresses or subnets to reach the port.
Event History
Frequently Asked Questions
What is the severity of CVE-2026-10831?
CVE-2026-10831 has a medium severity rating of 6.9.
How do I fix CVE-2026-10831?
To fix CVE-2026-10831, implement the recommended access controls and update the firmware of the affected NPort devices.
What impact does CVE-2026-10831 have on devices?
CVE-2026-10831 can lead to a denial-of-service condition due to improper authorization of break signal commands.
Which devices are affected by CVE-2026-10831?
CVE-2026-10831 affects MOXA NPort devices that utilize the command port for communication.
Can CVE-2026-10831 be exploited remotely?
Yes, CVE-2026-10831 can be exploited remotely by an attacker with network access to the affected devices.