CVE-2026-20405

Modem Manufacturer · Modem Firmware

Modem firmware is susceptible to a system crash due to a missing bounds check, which can be triggered by malformed input.

Executive summary

A missing bounds check in modem firmware allows for a system crash, creating a significant Denial of Service risk for the affected hardware.

Vulnerability

This vulnerability stems from a missing bounds check within the modem's firmware components. By sending crafted data that exceeds expected limits, an unauthenticated attacker can trigger a crash of the modem's operating system.

Business impact

The resulting system crash leads to a total loss of network availability for the affected device. The CVSS score of 7.5 reflects the high impact on business continuity, as communication failures can prevent access to cloud services, remote offices, and customer-facing applications.

Remediation

Immediate Action: Deploy the manufacturer's firmware update that specifically addresses the missing bounds check vulnerability.

Proactive Monitoring: Implement automated alerts for device downtime to ensure rapid response if a DoS attack occurs.

Compensating Controls: Use intrusion prevention systems (IPS) to detect and drop packets that exhibit characteristics of buffer overflow or bounds-violation attempts.

Exploitation status

Public Exploit Available: false

Analyst recommendation

Immediate patching is the only effective mitigation. IT administrators should verify the firmware versions of all deployed modems and update any that are running vulnerable software to prevent service interruptions.