CVE-2021-27461 in Rosemount X-STREAM Gas Analyzer
Summary
by MITRE • 05/21/2021
A vulnerability has been found in multiple revisions of Emerson Rosemount X-STREAM Gas Analyzer. The affected webserver applications allow access to stored data that can be obtained by using specially crafted URLs.
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Analysis
by VulDB Data Team • 05/23/2021
The vulnerability identified as CVE-2021-27461 affects Emerson Rosemount X-STREAM Gas Analyzer systems across multiple software revisions, representing a critical security flaw in industrial control systems. This vulnerability resides within the webserver applications that manage the analyzer's operational interface, creating a pathway for unauthorized data access through manipulated Uniform Resource Locators. The affected devices operate in critical infrastructure environments where gas analysis and monitoring are essential for safety and operational continuity, making this vulnerability particularly concerning for industrial security posture.
The technical flaw manifests as an insufficient access control mechanism within the webserver component of the Rosemount X-STREAM analyzer. Attackers can exploit this weakness by crafting specific URLs that bypass normal authentication and authorization procedures, gaining access to stored data that should otherwise be protected. This represents a classic path traversal or directory traversal vulnerability where the web application fails to properly validate user input before accessing internal resources. The vulnerability stems from inadequate input sanitization and insufficient privilege enforcement within the web interface, allowing malicious actors to construct URLs that traverse the application's file system or data access layers.
The operational impact of this vulnerability extends beyond simple data exposure, as it creates potential for significant disruption to industrial processes and safety systems. Unauthorized access to stored gas analysis data could compromise operational integrity, enable process tampering, or provide attackers with sensitive information about production parameters and environmental conditions. In industrial environments where these analyzers are deployed for critical safety monitoring, such access could lead to operational failures or safety hazards. The vulnerability also enables potential escalation to more serious attacks, as the initial data access could serve as a foothold for further exploitation within the industrial control network.
Mitigation strategies for CVE-2021-27461 should prioritize immediate software updates from Emerson to address the identified access control weaknesses. Organizations must implement network segmentation to isolate these industrial devices from general network access, applying firewall rules that restrict web server access to authorized personnel only. The implementation of web application firewalls can provide additional protection layers, monitoring for suspicious URL patterns that attempt to exploit the vulnerability. Security teams should conduct comprehensive network scans to identify all affected devices and ensure proper access controls are implemented through authentication mechanisms that enforce least privilege principles. Regular security assessments of industrial control systems should be performed to identify similar vulnerabilities, with adherence to standards such as those outlined in the CWE database under categories related to insufficient access control and improper input validation. The ATT&CK framework's methodology for industrial control systems should be considered when developing defensive strategies, particularly focusing on defense in depth approaches that protect against lateral movement and data exfiltration attempts. Organizations should also establish robust incident response procedures that account for potential exploitation of such vulnerabilities in critical infrastructure environments.