CVE-2024-52564: UD-LT1 Firmware RCE Vulnerability

CVE-2024-52564 Overview

CVE-2024-52564 affects IODATA UD-LT1 and UD-LT1/EX LTE routers running firmware version 2.1.8 and earlier. The vulnerability stems from an undocumented feature, sometimes referred to as a chicken bit, embedded in the device firmware [CWE-1242]. A remote attacker can leverage this hidden functionality over the network to disable the firewall function of the affected products. Once the firewall is disabled, the attacker can execute arbitrary operating system commands or modify device configuration settings. The vulnerability requires no authentication or user interaction and is exploitable across the network.

Critical Impact
Remote attackers can disable the firewall on UD-LT1 and UD-LT1/EX routers, enabling arbitrary OS command execution and unauthorized configuration changes without authentication.

Affected Products

IODATA UD-LT1 firmware version 2.1.8 and earlier
IODATA UD-LT1/EX firmware version 2.1.8 and earlier
LTE-capable business routers deployed with default firmware

Discovery Timeline

2024-12-05 - CVE-2024-52564 published to NVD
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2024-52564

Vulnerability Analysis

The UD-LT1 and UD-LT1/EX are cellular LTE routers manufactured by IODATA for business and remote-site connectivity. Both devices ship with firmware containing an undocumented feature that is not disclosed in vendor documentation. This class of weakness is classified under [CWE-1242], covering inclusion of undocumented features or chicken bits. Attackers who discover the hidden interface can invoke it remotely to disable protective controls on the device. The disabled firewall then exposes the underlying operating system to command execution and configuration tampering. The integrity impact is significant, while confidentiality and availability are not directly affected by the primary vector.

Root Cause

The root cause is the presence of hidden functionality that bypasses standard access controls in the router firmware. The undocumented interface accepts remote input and toggles security enforcement without requiring valid credentials. Because the feature is not documented, administrators cannot audit, disable, or monitor its use through standard configuration channels.

Attack Vector

An attacker sends crafted network requests to the affected router to invoke the undocumented feature. No prior authentication or user interaction is required. Once the firewall is disabled, the attacker issues follow-on requests that execute arbitrary OS commands or alter configuration values such as routing rules, DNS settings, or administrative credentials. Refer to the JVN Security Advisory and IODATA Support Information for vendor-provided technical detail.

Detection Methods for CVE-2024-52564

Indicators of Compromise

Unexpected firewall state changes on UD-LT1 or UD-LT1/EX devices, especially transitions from enabled to disabled without an administrative session.
Unusual outbound traffic from the router management interface or new listening services on the WAN side.
Configuration changes appearing in device logs without a corresponding authenticated administrative login.

Detection Strategies

Monitor router syslog output for firewall rule changes, service restarts, and configuration writes that lack a matching admin authentication event.
Baseline the network egress profile of each UD-LT1 device and alert on deviations such as new destination IPs, ports, or protocols.
Inspect inbound traffic to the router management plane for anomalous request patterns targeting undocumented endpoints.

Monitoring Recommendations

Forward router logs to a centralized SIEM or data lake for correlation with network flow telemetry.
Enable alerting on any change to firewall enable state or NAT rules on affected devices.
Periodically verify firmware version and configuration against a known-good baseline.

How to Mitigate CVE-2024-52564

Immediate Actions Required

Update UD-LT1 and UD-LT1/EX devices to the firmware version released by IODATA that remediates this issue, as described in the IODATA Support Information advisory.
Restrict WAN-side access to router management and service ports using upstream network controls until patching is complete.
Audit device configuration and firewall state on all affected units to confirm no unauthorized changes occurred.

Patch Information

IODATA has published remediation guidance for UD-LT1 and UD-LT1/EX. Apply the vendor-supplied firmware update that supersedes version 2.1.8. Consult the JVN Security Advisory for the coordinated disclosure details and the vendor page for exact firmware version numbers and installation instructions.

Workarounds

Place affected routers behind an upstream firewall that blocks untrusted inbound traffic to the device.
Disable remote management from untrusted networks and restrict administration to a dedicated management VLAN.
Rotate administrative credentials and review configuration integrity after applying network-layer restrictions.

bash

# Example upstream ACL to restrict access to router management until patched
# Replace <ROUTER_IP> and <MGMT_SUBNET> with environment-specific values
iptables -A FORWARD -s <MGMT_SUBNET> -d <ROUTER_IP> -j ACCEPT
iptables -A FORWARD -d <ROUTER_IP> -j DROP