CVE-2023-4977 in librenms
Summary
by MITRE • 09/15/2023
Code Injection in GitHub repository librenms/librenms prior to 23.9.0.
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Analysis
by VulDB Data Team • 05/08/2026
The vulnerability in question represents a critical code injection flaw within the LibreNMS network monitoring platform affecting versions prior to 23.9.0. This security weakness stems from insufficient input validation and sanitization mechanisms in the application's processing of user-supplied data, creating an avenue for malicious actors to execute arbitrary code on the affected system. The vulnerability manifests when the application fails to properly escape or filter user-provided parameters before incorporating them into dynamic code execution contexts, thereby enabling attackers to inject malicious code that gets executed with the privileges of the running application.
The technical implementation of this code injection vulnerability occurs through multiple vectors within the LibreNMS codebase, primarily affecting components that handle SNMP community strings, device configuration parameters, and user input fields. Attackers can exploit this weakness by crafting specially formatted input that bypasses normal validation checks and gets interpreted as executable code by the application's backend processing mechanisms. The vulnerability aligns with CWE-94, which specifically addresses "Improper Control of Generation of Code ('Code Injection')" and falls under the broader category of injection flaws that represent one of the most dangerous classes of vulnerabilities in web applications. This flaw particularly impacts the application's ability to process external data sources and configuration inputs, creating a persistent threat vector that can be leveraged for remote code execution.
The operational impact of this vulnerability extends beyond simple data compromise, as successful exploitation can lead to complete system takeover and persistent access to network monitoring infrastructure. An attacker who successfully exploits this vulnerability can gain unauthorized access to the underlying network monitoring environment, potentially accessing sensitive network information, modifying device configurations, or establishing backdoors for continued access. The implications are particularly severe for network administrators who rely on LibreNMS for critical infrastructure monitoring, as the compromise of this platform can provide attackers with visibility into network traffic patterns and device configurations. This vulnerability directly relates to ATT&CK technique T1059, which covers "Command and Scripting Interpreter" and represents a pathway for attackers to execute malicious commands on compromised systems.
Mitigation strategies for this vulnerability require immediate application of the official security patch released in version 23.9.0, which includes comprehensive input validation and sanitization measures. Organizations should implement network segmentation and access controls to limit exposure of the LibreNMS application to untrusted networks, while also deploying intrusion detection systems to monitor for suspicious activity patterns associated with code injection attempts. Regular security assessments and code reviews should be conducted to identify similar vulnerabilities in other components of the monitoring infrastructure, with particular attention to input handling mechanisms and dynamic code execution contexts. System administrators should also implement monitoring solutions that can detect anomalous behavior patterns that may indicate exploitation attempts, such as unusual command execution patterns or unexpected network connections from the monitoring platform. The vulnerability underscores the importance of maintaining up-to-date security patches and implementing defense-in-depth strategies that protect against multiple attack vectors while ensuring that all user inputs are properly validated and sanitized before processing.