CVE-2024-27771 Overview
CVE-2024-27771 is a path traversal vulnerability [CWE-22] affecting Unitronics Unistream UniLogic versions prior to 1.35.227. The flaw allows an authenticated network attacker to traverse directories outside the intended path scope. Successful exploitation can lead to remote code execution (RCE) on the affected controller software. UniLogic is the engineering software used to program Unitronics Unistream programmable logic controllers (PLCs), which are deployed in industrial and critical infrastructure environments. The vulnerability carries a CVSS 3.1 score of 8.8 and requires low privileges but no user interaction.
Critical Impact
Attackers with low-privileged network access can escape path restrictions and execute arbitrary code, compromising confidentiality, integrity, and availability of UniLogic environments.
Affected Products
- Unitronics UniLogic versions prior to 1.35.227
- Unitronics Unistream PLC engineering workflows using vulnerable UniLogic builds
- Industrial deployments relying on UniLogic project files and file-handling routines
Discovery Timeline
- 2024-03-18 - CVE-2024-27771 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2024-27771
Vulnerability Analysis
The vulnerability is a path traversal weakness in UniLogic. The software fails to properly neutralize sequences such as ../ in user-controlled file path inputs. An authenticated attacker with network access to the affected component can craft input that references files or directories outside of the intended working directory. Because UniLogic processes trusted project data with elevated context, traversal into writable locations can be chained into remote code execution. The attack vector is network-based with low attack complexity, which broadens the exposure across industrial engineering workstations and connected PLC environments.
Root Cause
The root cause is insufficient validation and canonicalization of file path parameters handled by UniLogic. When the application resolves file references, it does not sanitize traversal sequences or enforce a strict allow-list of base directories. This mirrors the classic CWE-22 pattern where untrusted input flows into file system APIs without normalization.
Attack Vector
An attacker authenticated to the UniLogic environment sends a crafted request containing traversal sequences in a file path field. The application resolves the path outside the intended directory, allowing the attacker to read, write, or overwrite files. Overwriting executable content, configuration, or auto-loaded resources yields code execution in the context of the UniLogic process. See the Claroty Team82 research on Unitronics Unistream vulnerabilities for technical background.
No verified public proof-of-concept code is available. Refer to vendor and researcher advisories for exploitation specifics.
Detection Methods for CVE-2024-27771
Indicators of Compromise
- File system artifacts in UniLogic working directories containing unexpected files written outside standard project paths
- Log entries showing file operations referencing sequences such as ../ or absolute paths outside the project scope
- Unexpected child processes spawned by UniLogic components on engineering workstations
Detection Strategies
- Monitor UniLogic project imports and file-handling operations for path components containing traversal patterns
- Inspect network traffic to UniLogic services for requests carrying encoded traversal sequences such as %2e%2e%2f
- Correlate authenticated UniLogic sessions with file-write events landing outside expected project directories
Monitoring Recommendations
- Enable verbose logging on engineering workstations running UniLogic and forward logs to a centralized SIEM
- Alert on process creation events where UniLogic parents unexpected binaries such as script interpreters or shells
- Baseline normal file operations for UniLogic and flag deviations, especially writes to system or startup locations
How to Mitigate CVE-2024-27771
Immediate Actions Required
- Upgrade UniLogic to version 1.35.227 or later on all engineering workstations
- Restrict network access to UniLogic services so only authorized operators can reach them
- Audit existing UniLogic accounts and enforce least-privilege access for project handling
Patch Information
Unitronics has addressed the vulnerability in UniLogic version 1.35.227. Operators should apply the update on every workstation used to program or manage Unistream PLCs. Additional context is available in the Israeli Government CVE advisory listing.
Workarounds
- Segment engineering workstations from general IT networks using firewall rules and industrial DMZ architecture
- Limit UniLogic project files to trusted sources and validate integrity before import
- Disable or restrict remote access paths that expose UniLogic to untrusted networks until patching is complete
# Example firewall restriction limiting UniLogic access to a trusted engineering subnet
iptables -A INPUT -p tcp --dport <unilogic-port> -s 10.10.20.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport <unilogic-port> -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
