CVE-2019-3953 in WebAccess
Summary
by MITRE
Stack-based buffer overflow in Advantech WebAccess/SCADA 8.4.0 allows a remote, unauthenticated attacker to execute arbitrary code by sending a crafted IOCTL 10012 RPC call.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 10/06/2023
The vulnerability identified as CVE-2019-3953 represents a critical stack-based buffer overflow flaw within Advantech WebAccess/SCADA version 8.4.0 that exposes organizations to significant remote execution risks. This vulnerability specifically manifests within the RPC handling mechanism of the SCADA system, where a maliciously crafted IOCTL 10012 call can trigger the buffer overflow condition. The flaw resides in the improper validation of input parameters within the remote procedure call processing logic, creating an exploitable condition that can be leveraged by attackers without requiring authentication credentials.
The technical implementation of this vulnerability follows a classic stack-based buffer overflow pattern where insufficient bounds checking allows an attacker to overwrite adjacent memory locations on the stack. The IOCTL 10012 RPC call serves as the attack vector, with the malicious input data exceeding the allocated buffer space and corrupting the stack frame. This corruption can overwrite return addresses, function pointers, and other critical stack variables, enabling an attacker to redirect program execution flow. The vulnerability directly maps to CWE-121 Stack-based Buffer Overflow, which is categorized under the broader category of memory safety issues in software development practices. The attack requires only network connectivity to the affected SCADA system, making it particularly dangerous in industrial environments where such systems often lack robust network segmentation.
The operational impact of this vulnerability extends beyond simple code execution, as it fundamentally compromises the integrity and availability of critical industrial control systems. In SCADA environments, the exploitation of this vulnerability could enable attackers to manipulate industrial processes, access sensitive operational data, or disrupt critical infrastructure operations. The unauthenticated nature of the attack means that any network-connected system running the vulnerable version of Advantech WebAccess/SCADA is immediately at risk without proper network controls or system hardening measures. This vulnerability aligns with ATT&CK technique T1210 for exploiting known vulnerabilities and T1059 for command and scripting interpreter, as the successful exploitation would likely involve executing malicious payloads through the compromised system.
Mitigation strategies for CVE-2019-3953 should focus on immediate patch deployment from Advantech, as well as network-level controls to restrict access to the affected services. Organizations should implement network segmentation to isolate SCADA systems from general corporate networks, deploy intrusion detection systems to monitor for suspicious RPC traffic patterns, and establish robust network access controls using firewalls and access control lists. Additionally, the implementation of principle of least privilege should be enforced, ensuring that only authorized personnel have access to the affected systems. The vulnerability highlights the importance of secure coding practices in industrial control systems and the necessity of regular security assessments for critical infrastructure components. Organizations should also consider implementing application whitelisting solutions and regular security audits to identify and remediate similar vulnerabilities in their industrial control system environments.