CVE-2021-30188 in CODESYS
Summary
by MITRE • 05/25/2021
CODESYS V2 runtime system SP before 2.4.7.55 has a Stack-based Buffer Overflow.
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Analysis
by VulDB Data Team • 08/15/2025
The vulnerability identified as CVE-2021-30188 affects the CODESYS V2 runtime system software development environment and runtime system that operates on industrial control systems and embedded devices. This particular flaw exists in versions prior to 2.4.7.55 of the CODESYS V2 runtime system, which is widely utilized in industrial automation and control applications. The affected system represents a critical component in many industrial environments where reliable and secure operation is paramount for safety and operational continuity. CODESYS V2 runtime systems are commonly deployed in manufacturing environments, process control systems, and other industrial applications that require robust software platforms for automation and control.
The technical flaw manifests as a stack-based buffer overflow vulnerability within the runtime system's handling of certain input data structures. This type of vulnerability occurs when a program writes more data to a buffer located on the stack than the buffer can accommodate, causing adjacent memory locations to be overwritten. The overflow typically happens during the processing of user-supplied input or data from external sources that the system receives and processes. The vulnerability specifically impacts how the system handles certain data processing routines where insufficient bounds checking occurs before writing data to stack-allocated memory regions. This weakness allows an attacker to potentially overwrite critical stack memory locations including return addresses, function pointers, or other control data that governs program execution flow.
The operational impact of this vulnerability extends significantly within industrial control environments where CODESYS V2 systems are deployed. An attacker who successfully exploits this buffer overflow could potentially execute arbitrary code on the affected system, leading to complete system compromise. The consequences could include unauthorized access to industrial control systems, data manipulation, disruption of manufacturing processes, or even physical damage to industrial equipment. This vulnerability directly impacts the integrity and availability of industrial control systems, potentially affecting critical infrastructure operations. The nature of industrial environments means that such exploitation could result in production halts, safety hazards, or security breaches that could affect entire facilities or supply chains.
Mitigation strategies for this vulnerability should begin with immediate application of the vendor-provided patch or update to version 2.4.7.55 or later. Organizations should conduct comprehensive vulnerability assessments to identify all systems running affected CODESYS V2 runtime versions and prioritize remediation efforts accordingly. Network segmentation and access controls should be implemented to limit exposure of these systems to untrusted networks or users. Additionally, monitoring systems should be deployed to detect unusual network traffic patterns or unauthorized access attempts that could indicate exploitation attempts. The vulnerability aligns with CWE-121, which describes stack-based buffer overflow conditions, and represents a significant risk within the industrial control systems domain. From an attack perspective, this vulnerability could be leveraged through techniques described in the MITRE ATT&CK framework under the T1059.001 technique for command and script interpreter, potentially allowing attackers to establish persistent access to industrial control environments. Organizations should also consider implementing intrusion detection systems specifically configured to monitor for patterns associated with buffer overflow exploitation attempts in industrial control environments.