Severity: Unknown
Description: A CWE-863: Incorrect Authorization vulnerability exists in U.motion Server (MEG6501-0001 - U.motion KNX server, MEG6501-0002 - U.motion KNX Server Plus, MEG6260-0410 - U.motion KNX Server Plus, Touch 10, MEG6260-0415 - U.motion KNX Server Plus, Touch 15), which could allow the file system to access the wrong file.
CVSS Score: N/A
D
No data available.
No data available.
1. Risk Assessment
The vulnerability, CVE-2019-6836, is an Incorrect Authorization (CWE-863) flaw within Schneider Electric’s U.motion Server products. This means that the system is not properly validating permissions when accessing files, potentially allowing a user or attacker to access files they shouldn’t. The EPSS score of 0.002800000 suggests a relatively low, but not insignificant, risk. The business impact depends heavily on what data is stored on the U.motion server and how critical it is. If the server stores configuration data, process parameters, or sensitive operational data, a successful exploit could disrupt operations or lead to incorrect control of KNX-enabled devices. Likelihood of exploitation is moderate; while not a readily exploitable vulnerability like a remote code execution, a determined attacker with appropriate access can leverage this flaw. Ease of exploitation is also moderate; it requires some understanding of the file system and permissions within the U.motion server. Potential impacts include a loss of confidentiality if sensitive files are accessed, a loss of integrity if files are modified incorrectly, and a loss of availability if crucial files are altered or rendered unusable.
2. Potential Attack Scenarios
An attacker with valid, but perhaps limited, access to the U.motion server could leverage the Incorrect Authorization vulnerability to gain access to files beyond their intended scope. For example, a user with read access to a configuration directory could potentially read files outside that directory, uncovering sensitive parameters or credentials.
The attack vector would be direct access to the U.motion server, potentially via a web interface or network share.
The attack process involves the attacker attempting to access files outside their authorized scope by specifying the correct file path. If the authorization check is flawed, the server will grant access.
The potential outcome is the exposure of sensitive configuration data, potentially including network settings, KNX device addresses, or even administrative credentials. This could lead to further compromise of the KNX network controlled by the U.motion server, allowing the attacker to manipulate lighting, HVAC, or other building automation systems.
3. Mitigation Recommendations
The primary mitigation is to apply the patch provided by Schneider Electric, as detailed in SEVD-2019-253-01: https://www.se.com/ww/en/download/document/SEVD-2019-253-01/. This patch should address the incorrect authorization checks, ensuring that users and processes only have access to the files they are authorized to access. As an immediate action, review the file system permissions on the U.motion server and restrict access to only those users and groups who require it. Implement regular file integrity monitoring to detect any unauthorized modifications. Consider network segmentation to isolate the U.motion server from other critical systems, limiting the impact of a potential compromise. Regularly review audit logs to identify any unusual file access patterns.
4. Executive Summary
Schneider Electric’s U.motion Server products are affected by a vulnerability that allows incorrect file access permissions. This means an attacker could potentially view or modify files they shouldn’t, potentially disrupting building automation systems. While the risk isn’t extremely high, the vulnerability could lead to loss of confidential data or incorrect control of connected devices. Applying the patch from Schneider Electric is the most effective way to address this issue. Prompt action is recommended to minimize the risk of disruption and maintain the integrity of your building automation infrastructure. The vulnerability represents a moderate risk to operations and should be prioritized for remediation, especially for installations where the U.motion server controls critical processes or holds sensitive data.
Severity: Unknown
Description: A CWE-863: Incorrect Authorization vulnerability exists in U.motion Server (MEG6501-0001 - U.motion KNX server, MEG6501-0002 - U.motion KNX Server Plus, MEG6260-0410 - U.motion KNX Server Plus, Touch 10, MEG6260-0415 - U.motion KNX Server Plus, Touch 15), which could allow a user with low privileges to delete a critical file.
CVSS Score: N/A
D
No data available.
No data available.
1. Risk Assessment
The vulnerability, CVE-2019-6838, is an Incorrect Authorization flaw within Schneider Electric's U.motion Server products. This means a user with relatively low privileges can delete a critical file within the system. The business impact could range from minor service disruption to complete system failure, depending on the criticality of the deleted file. The likelihood of exploitation is moderate, as it requires a user account with some level of access to the U.motion Server. The ease of exploitation is also moderate, as it depends on the specific file permissions and how the server is configured, but is not overly complex. The primary impact is to system integrity, as a critical file deletion can destabilize or halt operations. Availability will be impacted if the deleted file is essential for system functionality. Confidentiality is less directly impacted, but could be compromised if the deleted file contained sensitive information. The EPSS score of 0.001460000 indicates a relatively low, but non-negligible, probability of exploitation.
2. Potential Attack Scenarios
An attacker, possessing a standard user account on the U.motion Server, could leverage this vulnerability to disrupt building automation services. The attacker gains access to the U.motion server via the KNX network, and then identifies a critical system configuration file. Using their standard user account, they delete this file. This causes the U.motion Server to either crash, or fall back to default settings, impacting building controls such as lighting, HVAC, and security systems. This could result in inconvenience for building occupants, or in more serious scenarios, loss of critical control over key systems. The attacker doesn’t necessarily need advanced technical skills, simply access to the server and awareness of the vulnerability.
3. Mitigation Recommendations
The primary mitigation for CVE-2019-6838 is to apply the latest patch or firmware update provided by Schneider Electric. The specific update version will depend on the affected U.motion Server model (MEG6501-0001, MEG6501-0002, MEG6260-0410, MEG6260-0415). Refer to Schneider Electric's security advisory SEVD-2019-253-01 for detailed instructions and download links: https://www.se.com/ww/en/download/document/SEVD-2019-253-01/. As an interim measure, review file permissions on the U.motion Server and restrict write access to critical files for users who do not require it. Implement robust user access controls, following the principle of least privilege. Regularly monitor system logs for unexpected file deletions.
4. Executive Summary
CVE-2019-6838 is an Incorrect Authorization vulnerability affecting Schneider Electric's U.motion Server products. A user with standard access can potentially delete critical system files, leading to service disruption and potentially impacting building automation controls. While the risk is moderate, the impact on building operations—lighting, HVAC, and security—could be significant. Prompt patching with the latest firmware update from Schneider Electric is recommended to address this vulnerability. Failing to patch could result in downtime, operational inefficiencies, and potential inconvenience for building occupants. This vulnerability should be prioritized for remediation, particularly for critical infrastructure deployments.
Severity: Unknown
Description: A CWE-434: Unrestricted Upload of File with Dangerous Type vulnerability exists in U.motion Server (MEG6501-0001 - U.motion KNX server, MEG6501-0002 - U.motion KNX Server Plus, MEG6260-0410 - U.motion KNX Server Plus, Touch 10, MEG6260-0415 - U.motion KNX Server Plus, Touch 15), which could allow a user with low privileges to upload a rogue file.
CVSS Score: N/A
D
No data available.
No data available.
1. Risk Assessment
The vulnerability CVE-2019-6839 is a CWE-434: Unrestricted Upload of File with Dangerous Type, existing within Schneider Electric’s U.motion Server products. This means a user with relatively low privileges can upload a file that the server doesn’t properly validate, potentially leading to code execution or other malicious outcomes. The business impact is moderate to high, especially in environments where the U.motion server controls critical building automation or industrial processes. The likelihood of exploitation is considered moderate; attackers need to have some level of access to the U.motion server interface, but this isn’t necessarily privileged access. The ease of exploitation is also moderate, as it depends on the server's configuration and what file types are allowed. A successful exploit could compromise the confidentiality of data stored on the server, the integrity of the KNX network it controls, and potentially the availability of controlled systems if a malicious file disrupts server operation. The EPSS score of 0.00485 indicates a relatively low but present risk, given the broader threat landscape.
2. Potential Attack Scenarios
An attacker with a standard user account on the U.motion server could upload a malicious PHP webshell disguised as an image file (e.g., a JPG with a hidden PHP script). If the server allows PHP execution for uploaded files, the attacker could access and execute the webshell via a web browser, gaining remote code execution on the server. This allows the attacker to potentially control the KNX network connected to the U.motion server, leading to control of lighting, HVAC, or other building automation systems. The attack vector is through the U.motion server’s file upload functionality, often accessible via a web interface. The attack process involves crafting a malicious file, uploading it through the interface, and then accessing the file to execute the embedded code. The outcome could be full control of the server and the connected KNX network, leading to disruption of operations, data theft, or even physical impacts depending on what the KNX network controls.
3. Mitigation Recommendations
The primary mitigation is to apply the latest patch available from Schneider Electric, as outlined in security bulletin SEVD-2019-253-01 (https://www.se.com/ww/en/download/document/SEVD-2019-253-01/). Beyond patching, implement stricter file validation rules on the U.motion server. Specifically, limit the allowed file types to only those absolutely necessary and verify file extensions are consistently enforced. Consider implementing a whitelist of allowed file types rather than a blacklist. For immediate action, review the current file upload configurations and restrict permissions to the minimum required for functionality. Monitor the server logs for unusual file uploads or activity. Regularly scan the U.motion server for vulnerabilities using a vulnerability scanner.
4. Executive Summary
CVE-2019-6839 represents an unrestricted file upload vulnerability in Schneider Electric’s U.motion Server, potentially allowing attackers to upload and execute malicious files. This could lead to control of the connected KNX network, impacting building automation or industrial control processes. While the risk is moderate, a successful attack could compromise system availability, data confidentiality, and operational integrity. It is crucial to apply the vendor-provided patch from Schneider Electric (SEVD-2019-253-01) as soon as possible. Furthermore, implementing stricter file validation rules and monitoring server logs will help reduce the risk of exploitation. Addressing this vulnerability will protect critical infrastructure and ensure continued reliable operation of building and industrial systems.