CVE-2024-24781: Hima F30 Firmware DoS Vulnerability

CVE-2024-24781 Overview

CVE-2024-24781 is an uncontrolled resource consumption vulnerability ([CWE-400]) affecting multiple HIMA safety controller product lines. An unauthenticated remote attacker can flood a single Ethernet port with excessive traffic to exhaust device resources. The condition causes a denial of service (DoS) on the affected industrial safety controllers. The vulnerability requires no authentication, no user interaction, and is exploitable over the network. HIMA controllers are deployed in safety-critical industrial environments, so a DoS condition can disrupt process safety operations. The issue was published to the National Vulnerability Database (NVD) on February 13, 2024.

Critical Impact
An unauthenticated remote attacker can disable HIMA safety controllers by sending excessive traffic to a single Ethernet port, impacting availability of safety-critical industrial systems.

Affected Products

HIMA F30, F35, and F60 series firmware (03x_yy COM and CPU modules)
HIMA F-COM 01 and F-CPU 01 firmware
HIMA X-COM 01, X-COM 01 E, X-CPU 01, X-CPU 31, and X-SB 01 firmware

Discovery Timeline

2024-02-13 - CVE-2024-24781 published to NVD
2024-11-21 - Last updated in NVD database

Technical Details for CVE-2024-24781

Vulnerability Analysis

The vulnerability is classified as uncontrolled resource consumption under [CWE-400]. Affected HIMA controllers do not adequately throttle or rate-limit incoming Ethernet traffic on a single port. An attacker who can reach the device on the network can send a sustained high volume of traffic to one Ethernet interface. This traffic exhausts internal processing resources on the controller and disrupts normal operation. Because the impact is on availability of safety controllers, the consequence extends beyond the device itself to the industrial process it monitors and protects. The vulnerability affects confidentiality and integrity at no level, but causes high availability impact.

Root Cause

The root cause is the absence of effective resource controls on the Ethernet interface stack of the affected HIMA firmware. The controllers process incoming frames without bounded queues, traffic shaping, or per-source rate limiting sufficient to withstand a flood. When traffic volume exceeds processing capacity, the controller exhausts CPU, memory, or network buffer resources and ceases responding to legitimate traffic.

Attack Vector

Exploitation requires only network reachability to a single Ethernet port on the controller. The attacker sends a sustained, high-rate stream of traffic to that port. No credentials, no protocol-specific payloads, and no user interaction are needed. In flat operational technology (OT) networks or environments where controllers are exposed beyond a segmented zone, an attacker on the same broadcast domain or a routable upstream segment can trigger the condition. See the VDE Security Advisory VDE-2024-013 for vendor technical details.

Detection Methods for CVE-2024-24781

Indicators of Compromise

Sustained high-rate ingress traffic targeting a single Ethernet port on a HIMA controller.
Loss of cyclic communication or heartbeat from the controller to engineering and SCADA stations.
Controller diagnostic counters showing dropped frames, buffer exhaustion, or CPU saturation.

Detection Strategies

Baseline normal traffic volume per controller port and alert on deviations exceeding expected thresholds.
Monitor industrial protocol session health (for example, safetyEthernet/safeethernet) for unexpected disconnections.
Correlate network flow telemetry with controller availability events in the SIEM.

Monitoring Recommendations

Forward switch port statistics, NetFlow/IPFIX, and controller syslog into a centralized analytics platform.
Alert on packet-per-second spikes directed at OT device IPs or MAC addresses.
Track controller reachability via passive monitoring and report sustained communication loss to operators.

How to Mitigate CVE-2024-24781

Immediate Actions Required

Inventory all HIMA F-Series and X-Series controllers and identify firmware versions in use.
Restrict network access to controllers using firewalls, VLAN segmentation, and OT/IT boundary controls.
Apply firmware updates from HIMA as referenced in VDE Security Advisory VDE-2024-013.
Block untrusted hosts from reaching controller Ethernet ports at the switch and firewall layer.

Patch Information

HIMA addresses the vulnerability through firmware updates referenced in the VDE Security Advisory VDE-2024-013. Operators should contact HIMA support for the firmware version applicable to their controller model and coordinate updates during planned maintenance windows due to the safety-critical nature of the devices.

Workarounds

Place controllers behind an industrial firewall or data diode that enforces strict allow-lists and rate limiting.
Enable port security and storm control on managed switches connected to controller Ethernet ports.
Isolate the safety network from corporate and remote-access networks using a demilitarized zone (DMZ).
Disable or physically disconnect Ethernet ports that are not required for operation.

bash

# Example: switch-level rate limiting and storm control to mitigate flood traffic
interface GigabitEthernet0/1
 description Link to HIMA controller
 storm-control broadcast level pps 100
 storm-control multicast level pps 100
 storm-control unicast level pps 1000
 storm-control action shutdown
 switchport port-security
 switchport port-security maximum 1
 switchport port-security violation restrict