CVE-2011-4881 in webMI2ADS
Summary
by MITRE
The web server in Certec atvise webMI2ADS (aka webMI) before 2.0.2 does not properly check return values from functions, which allows remote attackers to cause a denial of service (NULL pointer dereference) via a crafted HTTP request.
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Analysis
by VulDB Data Team • 02/16/2025
The vulnerability identified as CVE-2011-4881 affects the Certec atvise webMI2ADS web server component, specifically within the webMI application version prior to 2.0.2. This issue represents a critical security flaw that stems from inadequate input validation and error handling mechanisms within the web server's processing logic. The affected system operates as a web-based interface for industrial automation and control systems, making it a potential target for attackers seeking to disrupt critical infrastructure operations. The vulnerability manifests when the web server fails to properly validate return values from internal functions, creating a pathway for malicious actors to exploit the system through carefully crafted HTTP requests.
The technical nature of this vulnerability falls under the category of improper error handling and null pointer dereference conditions, which are commonly classified as CWE-476 in the Common Weakness Enumeration framework. When the web server receives a malformed HTTP request, it attempts to process the request without adequate validation of function return values, leading to a situation where a NULL pointer is dereferenced during normal processing operations. This specific flaw represents a classic example of a denial of service vulnerability that can be triggered remotely, allowing attackers to crash the web server process and render the industrial automation interface unavailable to legitimate users.
The operational impact of this vulnerability extends beyond simple service disruption, particularly within industrial control environments where system availability is paramount. A successful exploitation of CVE-2011-4881 could result in complete unavailability of the webMI interface, preventing operators from accessing critical system controls, monitoring data, or configuring automation processes. This denial of service condition directly impacts the availability aspect of the CIA triad and can potentially lead to production downtime, operational inefficiencies, and increased maintenance costs. The vulnerability is particularly concerning in industrial settings where continuous operation is required and where the webMI interface serves as a primary means of system interaction and monitoring.
From a threat modeling perspective, this vulnerability aligns with ATT&CK technique T1499.004 which covers network denial of service attacks. The attack vector requires remote access through HTTP communications, making it accessible to attackers who can reach the target network through standard internet connectivity. The exploitation process involves crafting specific HTTP requests that trigger the NULL pointer dereference condition, which is a relatively simple attack to implement compared to more complex exploitation techniques. Organizations should consider implementing network segmentation and access controls to limit exposure of such industrial web interfaces to untrusted networks, while also ensuring that all industrial control systems receive regular security updates and patches to address known vulnerabilities. The remediation approach involves updating to webMI version 2.0.2 or later, which includes proper return value validation and error handling mechanisms that prevent the NULL pointer dereference condition from occurring during normal processing operations.