CVE-2024-14034: Hirschmann HiEOS Auth Bypass Vulnerability

CVE-2024-14034 Overview

CVE-2024-14034 is an authentication bypass vulnerability affecting Hirschmann HiEOS devices in the HTTP(S) management module. This critical vulnerability allows unauthenticated remote attackers to gain administrative access by sending specially crafted HTTP(S) requests to the target device. Attackers can exploit improper authentication handling to obtain elevated privileges and perform unauthorized actions including configuration download or upload and firmware modification.

Critical Impact

Unauthenticated attackers can gain full administrative control over affected Hirschmann HiEOS devices, enabling configuration tampering, firmware modification, and complete device compromise without requiring any credentials.

Affected Products

• Hirschmann HiEOS devices with HTTP(S) management module enabled
• Industrial network switches and devices running vulnerable HiEOS firmware versions

Discovery Timeline

• 2026-04-02 - CVE-2024-14034 published to NVD
• 2026-04-02 - Last updated in NVD database

Technical Details for CVE-2024-14034

Vulnerability Analysis

This vulnerability stems from improper authentication handling (CWE-287) in the HTTP(S) management interface of Hirschmann HiEOS devices. The authentication bypass allows remote attackers to circumvent security controls without providing valid credentials, effectively gaining administrative access to the device management interface.

Once exploited, attackers can perform actions typically restricted to authenticated administrators, including downloading device configurations that may contain sensitive network information, uploading malicious configurations, and modifying device firmware. This level of access in industrial network environments can have severe consequences for operational technology (OT) infrastructure.

The vulnerability is particularly concerning in industrial control system (ICS) environments where Hirschmann devices are commonly deployed for critical network infrastructure. Successful exploitation could allow attackers to pivot within industrial networks, disrupt operations, or establish persistent access.

Root Cause

The root cause of this vulnerability is improper authentication handling in the HTTP(S) management module. The authentication mechanism fails to properly validate requests, allowing specially crafted HTTP(S) requests to bypass authentication checks entirely. This implementation flaw enables unauthenticated users to access protected administrative functions.

Attack Vector

The attack vector is network-based, requiring no user interaction or prior authentication. An attacker with network access to the HTTP(S) management interface can send specially crafted requests to exploit the authentication bypass.

The exploitation process involves sending malformed or specially constructed HTTP(S) requests to the device's management interface. The improper authentication handling allows these requests to be processed as if they originated from an authenticated administrator, granting the attacker full administrative privileges on the target device.

For detailed technical information regarding the exploitation mechanism, refer to the Belden Security Bulletin BSECV-2024-02.

Detection Methods for CVE-2024-14034

Indicators of Compromise

• Unexpected administrative sessions or logins to HiEOS device management interfaces
• Configuration changes or firmware modifications without authorized administrator activity
• Unusual HTTP(S) traffic patterns to device management ports
• Unauthorized configuration downloads or uploads in device logs

Detection Strategies

• Monitor HTTP(S) traffic to HiEOS device management interfaces for anomalous request patterns
• Implement network segmentation monitoring to detect unauthorized access attempts to management interfaces
• Review device authentication logs for failed or suspicious authentication attempts
• Deploy intrusion detection systems (IDS) with rules targeting authentication bypass attempts on industrial devices

Monitoring Recommendations

• Enable comprehensive logging on HiEOS device management interfaces
• Implement network traffic analysis for industrial control system segments
• Configure alerts for configuration changes or firmware modifications on critical network devices
• Regularly audit device configurations for unauthorized modifications

How to Mitigate CVE-2024-14034

Immediate Actions Required

• Restrict network access to HiEOS device management interfaces using firewall rules and access control lists
• Isolate affected devices from untrusted networks, particularly the internet
• Implement network segmentation to limit exposure of management interfaces
• Monitor affected devices for signs of compromise while awaiting patches

Patch Information

Belden has released a security bulletin addressing this vulnerability. Administrators should consult the Belden Security Bulletin BSECV-2024-02 for specific patch information and updated firmware versions. Apply vendor-provided patches as soon as they become available for your device models.

Workarounds

• Disable HTTP(S) management interface access from untrusted networks if not required
• Implement VPN access requirements for remote management of affected devices
• Configure strict access control lists (ACLs) to limit management interface access to authorized IP addresses only
• Consider disabling web-based management and using alternative management methods until patches are applied

# Example network segmentation configuration
# Restrict management interface access to authorized management VLAN only
# Consult your firewall documentation for specific syntax

# Block external access to management ports
iptables -A INPUT -p tcp --dport 443 -s !192.168.100.0/24 -j DROP
iptables -A INPUT -p tcp --dport 80 -s !192.168.100.0/24 -j DROP