CVE-2012-4706 in CODESYS Gateway-Server
Summary
by MITRE
Integer signedness error in 3S CODESYS Gateway-Server before 2.3.9.27 allows remote attackers to cause a denial of service via a crafted packet that triggers a heap-based buffer overflow.
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Analysis
by VulDB Data Team • 04/25/2017
The vulnerability identified as CVE-2012-4706 represents a critical integer signedness error within the 3S CODESYS Gateway-Server software version 2.3.9.27 and earlier. This flaw exists in the network protocol handling mechanisms where the software fails to properly validate integer values during packet processing, creating a condition that can be exploited by remote attackers to execute malicious code. The issue stems from improper handling of signed and unsigned integer comparisons, which is a well-documented weakness in software development practices and aligns with CWE-191, which specifically addresses signed integer underflow conditions. The vulnerability affects the gateway server's ability to process incoming network packets, particularly those containing malformed data structures that manipulate integer values in unexpected ways.
The technical exploitation of this vulnerability occurs when a remote attacker crafts a specially designed packet that contains integer values which, when processed by the vulnerable software, cause arithmetic operations to produce unexpected results. These malformed packets trigger a heap-based buffer overflow condition within the memory management system of the CODESYS Gateway-Server. The buffer overflow occurs because the software incorrectly calculates buffer sizes based on the flawed integer arithmetic, leading to memory corruption that can be leveraged to crash the application or potentially execute arbitrary code. This type of vulnerability falls under the ATT&CK framework's technique T1059 for command and script injection, as successful exploitation could allow attackers to gain unauthorized access to the system.
The operational impact of this vulnerability extends beyond simple denial of service conditions, as it represents a potential entry point for more sophisticated attacks. Organizations relying on 3S CODESYS Gateway-Server for industrial control systems, building automation, or manufacturing processes face significant risks when this vulnerability remains unpatched. The heap-based buffer overflow could result in system instability, complete service interruption, or in more severe cases, provide attackers with a foothold for further reconnaissance and lateral movement within network environments. The vulnerability's remote exploitability means that attackers do not require physical access to the system, making it particularly dangerous for operational technology environments where security controls may be less stringent than in traditional enterprise networks.
Mitigation strategies for CVE-2012-4706 should prioritize immediate patch deployment to version 2.3.9.27 or later, which contains the necessary fixes for the integer signedness error. Network segmentation and firewall rules should be implemented to restrict access to the affected gateway server, limiting the attack surface and preventing unauthorized access attempts. Additionally, implementing network monitoring solutions that can detect anomalous packet patterns and malformed traffic can help identify potential exploitation attempts. Security teams should also conduct thorough vulnerability assessments of their industrial control systems to identify any other instances of the same vulnerability pattern within their infrastructure. The remediation process should include comprehensive testing of the updated software to ensure that the patch does not introduce compatibility issues with existing industrial processes or control systems, as operational technology environments often have strict requirements for system stability and reliability that must be maintained during security updates.