CVE-2018-4842 in Scalance X-200 IRT
Summary
by MITRE
A vulnerability has been identified in SCALANCE X-200 IRT (All versions < V5.4.1), SCALANCE X300 (All versions). A remote, authenticated attacker with access to the configuration web server could be able to store script code on the web site, if the HRP redundancy option is set. This code could be executed in the web browser of victims visiting this web site (XSS), affecting its confidentiality, integrity and availability. User interaction is required for successful exploitation, as the user needs to visit the manipulated web site.
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Analysis
by VulDB Data Team • 03/27/2023
The vulnerability identified as CVE-2018-4842 affects Siemens SCALANCE X-200 IRT and SCALANCE X300 industrial network devices, specifically impacting versions prior to V5.4.1. This security flaw represents a critical cross-site scripting vulnerability that arises from improper input validation within the web-based configuration interface of these industrial communication devices. The vulnerability is particularly concerning in industrial control systems environments where these devices are commonly deployed for network infrastructure management and monitoring purposes.
The technical implementation of this vulnerability stems from the device's handling of web content when the HRP (High Availability Redundancy Protocol) redundancy option is enabled. When an authenticated attacker gains access to the device's configuration web server, they can inject malicious script code into the web interface. This injection occurs because the system fails to properly sanitize user-supplied input before storing and rendering it within the web browser context. The flaw specifically manifests when the HRP redundancy feature is active, suggesting that the vulnerability is tied to how the device handles redundant configuration data within its web server components.
The operational impact of this vulnerability extends beyond typical web application security concerns, as it affects industrial control systems where device integrity and availability are paramount. An attacker who successfully exploits this vulnerability can execute arbitrary scripts in the web browser of any user who visits the compromised web interface. This creates a significant risk to the confidentiality of sensitive operational data, as attackers could potentially steal session cookies, capture user credentials, or exfiltrate information from the industrial network. The integrity of the device's web interface and configuration data becomes compromised, potentially allowing attackers to manipulate network settings or redirect traffic. Availability is also at risk as the malicious scripts could cause browser crashes or render the web interface unusable.
The exploitation of this vulnerability requires user interaction, meaning that a successful attack depends on tricking users into visiting the maliciously modified web page. This requirement somewhat limits the automatic exploitation potential but does not eliminate the threat, as social engineering attacks can effectively target personnel with access to these industrial devices. The vulnerability is classified as a cross-site scripting attack under CWE-79, which specifically addresses the improper sanitization of user-supplied data in web applications. This vulnerability also aligns with ATT&CK technique T1059.006 for Command and Scripting Interpreter, as attackers could potentially use this vector to execute malicious scripts on compromised systems.
Mitigation strategies for CVE-2018-4842 should prioritize immediate firmware updates to versions V5.4.1 or later, which contain the necessary patches to address the input validation flaws. Network segmentation should be implemented to limit access to these devices to authorized personnel only, reducing the attack surface for potential exploitation. Access controls must be strengthened through the implementation of multi-factor authentication and role-based access restrictions. Additionally, network monitoring should be enhanced to detect unusual traffic patterns that might indicate exploitation attempts. Security awareness training for personnel who manage these industrial devices should emphasize the importance of not visiting untrusted web pages and recognizing social engineering attempts that could lead to credential compromise. Organizations should also implement regular security assessments of their industrial control systems to identify and remediate similar vulnerabilities before they can be exploited by threat actors.