CVE-2019-20376 in Electronic Logbook
Summary
by MITRE
A cross-site scripting (XSS) vulnerability in Electronic Logbook (ELOG) 3.1.4 allows remote attackers to inject arbitrary web script or HTML via a crafted SVG document to elogd.c.
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Analysis
by VulDB Data Team • 03/20/2024
The vulnerability identified as CVE-2019-20376 represents a critical cross-site scripting flaw within the Electronic Logbook (ELOG) version 3.1.4 system. This vulnerability specifically affects the elogd.c component which serves as a core daemon for processing and handling log entries. The security weakness arises from insufficient input validation and sanitization mechanisms when processing SVG (Scalable Vector Graphics) documents, creating an avenue for malicious actors to execute arbitrary web scripts or HTML code within the context of affected user sessions. The Electronic Logbook system is widely utilized for maintaining operational records and log management in various industrial and research environments, making this vulnerability particularly concerning for organizations relying on its functionality. The flaw exists in the daemon's processing logic where SVG files are accepted and rendered without proper security measures to prevent malicious content injection, potentially allowing attackers to exploit this weakness through crafted SVG documents that contain embedded scripts or malicious code.
The technical exploitation of this vulnerability occurs through the improper handling of SVG file inputs within the elogd.c daemon process. When the system processes an SVG document containing malicious script elements, the lack of input validation allows these scripts to be executed within the browser context of legitimate users who view the log entries. This type of vulnerability maps directly to CWE-79 - Improper Neutralization of Input During Web Page Generation, which specifically addresses the failure to sanitize user-controllable data before it is used in web page generation. The attack vector involves remote code execution through web-based interfaces where SVG documents are rendered as part of the log display functionality. The vulnerability demonstrates a classic XSS pattern where the attacker crafts an SVG file containing embedded JavaScript or HTML content that gets executed when the file is viewed by other users within the ELOG system. This processing chain creates an environment where user-supplied content bypasses all security controls and directly influences the client-side execution context, making it particularly dangerous in multi-user environments where log entries are shared across different security levels.
The operational impact of CVE-2019-20376 extends beyond simple script execution, potentially allowing attackers to perform session hijacking, data exfiltration, and privilege escalation within the affected system. An attacker could leverage this vulnerability to steal session cookies, redirect users to malicious websites, or inject additional malicious content into the log entries, which would then be visible to other system users. The implications are particularly severe in industrial control systems or research environments where Electronic Logbook systems are used for critical operations, as this vulnerability could compromise operational integrity and potentially enable further attacks on connected systems. Organizations using ELOG 3.1.4 may face unauthorized access to sensitive operational data, disruption of log management processes, and potential compromise of the broader network infrastructure through credential theft or lateral movement. The vulnerability affects the core functionality of the system's document processing capabilities, which means that any log entry containing malicious SVG content could serve as a persistent threat vector. This type of vulnerability also aligns with ATT&CK technique T1566 - Phishing with Malicious Attachments, as the attack could be delivered through SVG files that appear legitimate but contain malicious payloads, and T1213 - Data from Information Repositories, as the compromised system could be used to access or manipulate stored log data.
Mitigation strategies for CVE-2019-20376 should focus on immediate remediation through software updates to the ELOG system, as the vulnerability has been addressed in subsequent releases. Organizations should implement strict input validation and sanitization measures for all SVG content, including the use of SVG-specific sanitization libraries and the enforcement of Content Security Policy (CSP) headers to prevent script execution in web contexts. Network-level protections such as web application firewalls should be configured to filter suspicious SVG content and monitor for known malicious patterns. Additionally, security teams should conduct comprehensive vulnerability assessments of all ELOG installations and implement proper access controls to limit the impact of potential exploitation. The remediation process should include thorough testing of updated software versions to ensure that the vulnerability is properly addressed without introducing regressions in system functionality. Organizations should also establish monitoring procedures to detect potential exploitation attempts and maintain updated threat intelligence feeds to identify emerging attack patterns targeting similar vulnerabilities in industrial control systems. Regular security audits of log management systems and user access controls are essential to prevent unauthorized modifications to log entries and maintain the integrity of operational records.