CVE-2018-7770 in U.motion Builder
Summary
by MITRE
The vulnerability exists within processing of sendmail.php in Schneider Electric U.motion Builder software versions prior to v1.3.4. The applet allows callers to select arbitrary files to send to an arbitrary email address.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 02/24/2020
The vulnerability identified as CVE-2018-7770 resides within Schneider Electric U.motion Builder software versions prior to v1.3.4, specifically within the sendmail.php application component. This flaw represents a critical security weakness that enables unauthorized users to manipulate the email sending functionality and potentially compromise the system's integrity. The vulnerability stems from inadequate input validation and access control mechanisms within the web application layer, allowing malicious actors to exploit the file selection and email delivery processes without proper authorization. The affected software is commonly used in industrial automation environments where security is paramount, making this vulnerability particularly concerning for operational technology infrastructure.
The technical implementation of this vulnerability manifests through improper sanitization of user inputs in the sendmail.php script, which processes email requests from the U.motion Builder application. Attackers can leverage this weakness to construct malicious email requests that reference arbitrary files stored on the server filesystem, potentially enabling them to access sensitive data or system resources. The flaw operates by allowing unauthenticated or unauthorized users to manipulate parameters that control file selection and destination email addresses, effectively bypassing the intended access controls. This vulnerability is classified as a path traversal or file inclusion issue under CWE-22, where the application fails to properly validate file paths and user inputs before processing email requests. The attack vector typically involves crafting specially formatted requests that exploit the lack of proper input validation in the email sending functionality.
The operational impact of CVE-2018-7770 extends beyond simple data exposure, as it can enable more sophisticated attacks within industrial control systems where U.motion Builder is deployed. An attacker who successfully exploits this vulnerability could potentially gain access to configuration files, system logs, or other sensitive data stored on the server. The implications are particularly severe in industrial environments where the software is used for building and managing automation systems, as this could lead to disruption of critical processes or unauthorized access to operational data. The vulnerability may also facilitate further exploitation attempts, such as attempting to send malicious attachments or leveraging the compromised email functionality for lateral movement within the network. This aligns with ATT&CK technique T1078.004 which describes valid accounts being used to access systems, and T1566 which covers spearphishing with a malicious attachment.
Organizations utilizing Schneider Electric U.motion Builder software should prioritize immediate remediation through the application of the vendor-provided patch or upgrade to version 1.3.4 and later. The mitigation strategy should include implementing proper input validation controls, restricting access to the sendmail.php functionality, and conducting thorough security assessments of the application's web interfaces. Network segmentation and access control measures should be strengthened to limit exposure of the vulnerable application to unauthorized users. Additionally, organizations should implement monitoring solutions to detect anomalous email sending activities that could indicate exploitation attempts. The vulnerability demonstrates the importance of secure coding practices and proper input validation in web applications, particularly those deployed in critical infrastructure environments where the consequences of exploitation can be severe. Regular security assessments and vulnerability management processes should be maintained to identify and remediate similar weaknesses in industrial control system software.