CVE-2024-27768: Unitronics Unilogic RCE Vulnerability

CVE-2024-27768 Overview

CVE-2024-27768 is a critical path traversal vulnerability (CWE-22) affecting Unitronics Unistream Unilogic software in versions prior to 1.35.227. This vulnerability allows unauthenticated attackers to exploit improper path validation to traverse directories and potentially achieve remote code execution (RCE) on affected systems. Given that Unitronics PLCs are commonly deployed in critical infrastructure environments including water treatment facilities and industrial control systems, this vulnerability poses significant risk to operational technology (OT) networks.

Critical Impact

Unauthenticated remote attackers can exploit path traversal to execute arbitrary code on Unitronics Unistream devices, potentially compromising industrial control systems and critical infrastructure.

Affected Products

• Unitronics Unilogic versions prior to 1.35.227
• Unitronics Unistream devices running vulnerable Unilogic software

Discovery Timeline

• 2024-03-18 - CVE-2024-27768 published to NVD
• 2025-03-10 - Last updated in NVD database

Technical Details for CVE-2024-27768

Vulnerability Analysis

This vulnerability stems from a path traversal weakness (CWE-22) in the Unitronics Unilogic software. Path traversal vulnerabilities occur when an application fails to properly validate or sanitize user-supplied input that specifies file paths, allowing attackers to access files and directories outside the intended scope.

In the context of Unitronics Unistream devices, an attacker can craft malicious requests containing directory traversal sequences (such as ../) to escape the application's designated directory structure. When successfully exploited, this can lead to arbitrary file read, file write, or in the worst case, remote code execution on the target system.

The network-accessible nature of this vulnerability is particularly concerning for industrial control system (ICS) environments. Programmable Logic Controllers (PLCs) like Unitronics Unistream devices often control physical processes in manufacturing, water treatment, and other critical infrastructure sectors. Unauthorized code execution on these devices could result in operational disruption, safety hazards, or physical damage to controlled processes.

Root Cause

The root cause of CVE-2024-27768 is insufficient input validation in the file path handling mechanisms of Unitronics Unilogic software. The application fails to properly sanitize or restrict user-controllable input used in file system operations, allowing directory traversal sequences to be processed. This improper neutralization of special path elements enables attackers to break out of the intended directory context and access arbitrary locations on the file system, potentially leading to code execution.

Attack Vector

The attack vector for CVE-2024-27768 is network-based, requiring no authentication or user interaction. An attacker with network access to a vulnerable Unitronics Unistream device can exploit this vulnerability by sending specially crafted requests containing path traversal sequences.

The attack typically involves:

1. Identifying a vulnerable Unitronics Unistream device accessible over the network
2. Crafting malicious input containing directory traversal sequences to escape intended file path restrictions
3. Leveraging the path traversal to access, modify, or upload files in sensitive locations
4. Achieving code execution by overwriting configuration files, uploading malicious scripts, or manipulating PLC logic

Detailed technical exploitation information is available in the Claroty Team82 Blog Post.

Detection Methods for CVE-2024-27768

Indicators of Compromise

• Unusual file access patterns or requests containing path traversal sequences (e.g., ../, ..\\) targeting Unistream devices
• Unexpected file modifications in PLC configuration directories or system folders
• Anomalous network traffic to Unitronics devices from unauthorized sources
• Unauthorized changes to PLC programming or logic files

Detection Strategies

• Deploy ICS-aware intrusion detection systems (IDS) to monitor network traffic for path traversal patterns in requests to Unitronics devices
• Implement file integrity monitoring on critical Unistream device configurations to detect unauthorized modifications
• Configure network segmentation with proper logging at boundary firewalls to track access attempts to OT networks
• Leverage SentinelOne Singularity platform for endpoint protection and behavioral analysis on engineering workstations that communicate with PLCs

Monitoring Recommendations

• Establish baseline network communication patterns for Unitronics devices and alert on deviations
• Monitor authentication logs and access attempts to Unistream devices for unauthorized access
• Implement centralized logging for all OT network traffic with automated alerting for suspicious file operation requests
• Conduct regular vulnerability assessments and configuration audits of PLC infrastructure

How to Mitigate CVE-2024-27768

Immediate Actions Required

• Upgrade Unitronics Unilogic software to version 1.35.227 or later immediately
• Isolate Unitronics Unistream devices from direct internet access and untrusted networks
• Implement network segmentation to restrict access to PLC devices to authorized engineering workstations only
• Enable logging and monitoring on all network paths to industrial control systems
• Review and audit existing PLC configurations for signs of unauthorized modification

Patch Information

Unitronics has addressed this vulnerability in Unilogic version 1.35.227 and later. Organizations should prioritize upgrading all affected Unitronics Unistream devices to the patched version. For detailed patch information and guidance, refer to the Israeli Government CVE Advisories and the Claroty Team82 Blog Post.

Workarounds

• If immediate patching is not feasible, implement strict network access controls to limit connectivity to Unistream devices from trusted sources only
• Deploy application-layer firewalls or web application firewalls (WAF) configured to block path traversal sequences in requests to PLCs
• Disable unnecessary network services on Unitronics devices to reduce attack surface
• Implement VPN or jump server requirements for all remote access to OT networks containing vulnerable devices

# Network segmentation example - restrict PLC access to authorized workstations
# Example iptables rules for engineering workstation access control
iptables -A INPUT -s 10.10.50.0/24 -d 10.10.100.0/24 -p tcp --dport 22 -j ACCEPT
iptables -A INPUT -s 10.10.50.0/24 -d 10.10.100.0/24 -p tcp --dport 502 -j ACCEPT
iptables -A INPUT -d 10.10.100.0/24 -j DROP