CVE-2011-5007 in CoDeSys
Summary
by MITRE
Stack-based buffer overflow in the CmpWebServer component in 3S CoDeSys 3.4 SP4 Patch 2 and earlier, as used on the ABB AC500 PLC and possibly other products, allows remote attackers to execute arbitrary code via a long URI to TCP port 8080.
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Analysis
by VulDB Data Team • 05/25/2025
The CVE-2011-5007 vulnerability represents a critical stack-based buffer overflow flaw within the CmpWebServer component of 3S CoDeSys 3.4 SP4 Patch 2 and earlier versions. This vulnerability specifically affects industrial control systems including the ABB AC500 PLC and potentially other similar products. The flaw exists in the web server implementation that handles HTTP requests on TCP port 8080, making it accessible to remote attackers without authentication requirements. The vulnerability stems from inadequate input validation mechanisms that fail to properly check the length of Uniform Resource Identifiers submitted by clients, creating an exploitable condition where attacker-controlled data can overwrite adjacent memory locations on the stack.
The technical exploitation of this vulnerability follows a classic buffer overflow pattern where a maliciously crafted URI exceeding the allocated buffer space causes a stack overflow condition. When the web server processes a long URI, the excessive input overflows the designated stack buffer and corrupts adjacent memory, potentially overwriting return addresses, function pointers, or other critical control data. This memory corruption can be leveraged by attackers to redirect program execution flow and inject malicious code into the target system. The vulnerability is particularly concerning in industrial environments where these systems operate without traditional security controls, making successful exploitation more likely to result in complete system compromise.
The operational impact of CVE-2011-5007 extends beyond simple code execution to encompass potential disruption of critical industrial processes and unauthorized access to sensitive operational data. In the context of ABB AC500 PLC systems, successful exploitation could allow attackers to manipulate industrial control logic, potentially causing physical damage to equipment, disruption of production processes, or unauthorized access to operational parameters. The remote nature of the attack means that adversaries can target these systems from outside the industrial network perimeter, potentially bypassing traditional network security controls. This vulnerability aligns with CWE-121 Stack-based Buffer Overflow and represents a significant risk in the industrial control systems landscape where cybersecurity maturity is often lower than in enterprise environments.
Mitigation strategies for CVE-2011-5007 should prioritize immediate remediation through official vendor patches and updates to 3S CoDeSys versions that address the buffer overflow condition. Organizations should implement network segmentation to isolate affected industrial control systems from general network access, particularly blocking access to TCP port 8080 from untrusted networks. Additional defensive measures include implementing network access controls to restrict access to the affected web server component, monitoring for suspicious URI patterns, and conducting regular security assessments of industrial control systems. The vulnerability demonstrates the importance of applying security patches promptly in industrial environments and aligns with ATT&CK techniques related to remote code execution and privilege escalation through software vulnerabilities. Organizations should also consider implementing industrial network monitoring solutions that can detect anomalous traffic patterns indicative of exploitation attempts against industrial control systems.