CVE-2018-19760 in libConfuse
Summary
by MITRE
cfg_init in confuse.c in libConfuse 3.2.2 has a memory leak.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 04/16/2020
The vulnerability identified as CVE-2018-19760 resides within the libConfuse library version 3.2.2, specifically within the cfg_init function located in the confuse.c source file. This memory leak represents a critical security flaw that can lead to resource exhaustion and potential system instability. The libConfuse library serves as a configuration file parsing library widely used in various software applications for handling configuration data structures. When the cfg_init function processes configuration files, it fails to properly release allocated memory resources, creating a persistent memory leak that accumulates over time. This vulnerability falls under the category of memory management errors and aligns with CWE-401, which specifically addresses "Improper Release of Memory Before Removing Last Reference" in the Common Weakness Enumeration catalog.
The technical implementation of this flaw occurs during the initialization phase of configuration parsing where the function allocates memory for internal data structures but does not consistently free this memory when processing multiple configuration files or repeated initialization calls. Attackers can exploit this vulnerability by repeatedly invoking the configuration initialization function or by processing large numbers of configuration files, causing the application to consume increasing amounts of memory until system resources are exhausted. The operational impact extends beyond simple resource consumption, as this memory leak can lead to application crashes, denial of service conditions, and potentially affect system stability when the vulnerable library is used in critical infrastructure applications. This vulnerability is particularly concerning because it affects the foundational configuration handling mechanism that many applications depend upon for proper operation.
The exploitation of CVE-2018-19760 can be categorized under ATT&CK technique T1499, which involves resource exhaustion attacks targeting memory availability. The vulnerability demonstrates characteristics of a persistent denial of service condition where legitimate users or processes may be denied access to system resources due to memory consumption. System administrators and security teams should prioritize patching affected systems as the fix typically involves proper memory management practices including ensuring that all allocated memory is freed before function termination. The remediation strategy involves updating to a patched version of libConfuse where the cfg_init function properly implements memory deallocation routines. Organizations using this library in production environments must conduct thorough vulnerability assessments to identify all applications that may be vulnerable, as the memory leak could be triggered through various application pathways including web interfaces, command-line tools, or system services that rely on configuration file parsing. The vulnerability represents a classic example of how seemingly minor memory management issues can escalate into significant security concerns when applications are subjected to sustained or repeated usage patterns.