CVE-2024-39373: Markoni Markoni-d Firmware RCE Vulnerability

CVE-2024-39373 Overview

CVE-2024-39373 is a command injection vulnerability affecting TELSAT marKoni FM transmitters. Attackers can manipulate device settings to inject operating system commands. Successful exploitation grants unauthorized administrative access to the transmitter system. The flaw is classified under [CWE-77] (Improper Neutralization of Special Elements used in a Command).

The vulnerability is remotely exploitable over the network without authentication or user interaction. Because marKoni transmitters are broadcast-critical equipment, exploitation can disrupt radio operations or enable attacker-controlled audio output. CISA published advisory ICSA-24-179-01 to coordinate disclosure.

Critical Impact

Unauthenticated remote command injection grants full administrative control over affected FM transmitters, enabling broadcast manipulation, configuration tampering, and persistent system compromise.

Affected Products

• Markoni Markoni-D (Compact) FM Transmitter firmware
• Markoni Markoni-DH (Exciter+Amplifiers) FM Transmitter firmware
• All firmware versions prior to vendor remediation

Discovery Timeline

• 2024-06-27 - CVE-2024-39373 published to NVD and CISA advisory ICSA-24-179-01 released
• 2026-06-17 - Last updated in NVD database

Technical Details for CVE-2024-39373

Vulnerability Analysis

The vulnerability resides in the administrative interface of marKoni FM transmitters. The device accepts configuration settings from network clients without properly neutralizing shell metacharacters. When the firmware processes these settings, attacker-supplied input is concatenated into a command string and passed to a system shell for execution.

Because the transmitter runs the management daemon with elevated privileges, injected commands execute with administrative rights. This grants the attacker complete control over the broadcast device, including the ability to modify transmission parameters, exfiltrate configuration data, or pivot deeper into the operational technology network.

The vulnerability carries network-based exploitation characteristics with no authentication or user interaction required, as reflected in the published CISA advisory.

Root Cause

The root cause is improper neutralization of special elements within configuration setting handlers [CWE-77]. The firmware fails to validate, escape, or whitelist input characters before passing them to a command interpreter. Shell metacharacters such as semicolons, backticks, pipes, and command substitution sequences are interpreted rather than treated as literal data.

Attack Vector

An attacker reaches the transmitter management interface over the network. The attacker submits crafted setting values containing shell metacharacters and injected commands. The firmware concatenates the malicious payload into an internal command and executes it with administrative privileges, granting persistent control. Technical exploitation details are described in CISA ICS Advisory ICSA-24-179-01.

Detection Methods for CVE-2024-39373

Indicators of Compromise

• Unexpected administrative sessions or configuration changes on marKoni transmitter management interfaces
• Outbound network connections from the transmitter to unfamiliar external hosts
• Setting fields that contain shell metacharacters such as ;, |, &&, backticks, or $() sequences
• Modifications to broadcast parameters, audio sources, or RDS data not initiated by authorized operators

Detection Strategies

• Inspect HTTP and management protocol traffic to the transmitter for setting parameters containing shell metacharacters
• Baseline normal configuration values and alert on out-of-policy changes to broadcast or system parameters
• Correlate device authentication events with network source addresses to identify unauthorized administrative access

Monitoring Recommendations

• Forward syslog and management interface logs from marKoni devices to a centralized SIEM for correlation
• Use OT-aware network monitoring to flag command-injection payload patterns directed at transmitter IPs
• Monitor egress from the broadcast OT segment for unauthorized outbound flows that may indicate post-exploitation activity

How to Mitigate CVE-2024-39373

Immediate Actions Required

• Restrict network access to marKoni transmitter management interfaces using strict firewall ACLs and management VLANs
• Remove any internet exposure of the transmitter management interface and verify with external attack surface scans
• Rotate administrative credentials and review recent configuration changes for unauthorized modifications
• Contact TELSAT marKoni for firmware updates and apply vendor-supplied patches once available

Patch Information

Refer to CISA ICS Advisory ICSA-24-179-01 for the latest vendor remediation guidance. Operators should coordinate directly with TELSAT marKoni to obtain firmware updates that neutralize shell metacharacters in configuration setting handlers.

Workarounds

• Place transmitters behind a jump host or VPN that enforces multi-factor authentication for administrative access
• Apply network segmentation to isolate broadcast OT equipment from corporate IT networks
• Disable any unused management services and protocols on the transmitter to reduce attack surface
• Implement intrusion prevention signatures that block command-injection payload patterns in management traffic

# Example firewall restriction (Linux iptables) limiting management access
# Replace MGMT_HOST and TRANSMITTER_IP with your environment values
iptables -A FORWARD -s MGMT_HOST -d TRANSMITTER_IP -p tcp --dport 80 -j ACCEPT
iptables -A FORWARD -s MGMT_HOST -d TRANSMITTER_IP -p tcp --dport 443 -j ACCEPT
iptables -A FORWARD -d TRANSMITTER_IP -j DROP