CVE-2019-6502 in OpenSC
Summary
by MITRE
sc_context_create in ctx.c in libopensc in OpenSC 0.19.0 has a memory leak, as demonstrated by a call from eidenv.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 07/02/2023
The vulnerability identified as CVE-2019-6502 resides within the OpenSC project's library component known as libopensc, specifically within the sc_context_create function located in the ctx.c file. This memory leak affects version 0.19.0 of the OpenSC software, which is a widely used open-source library for smart card communication and cryptographic operations. The flaw manifests when the function is invoked through the eidenv utility, which is commonly used for environment variable management in smart card applications. The memory leak represents a critical issue that can lead to resource exhaustion over time, particularly in systems where the affected function is called repeatedly or in long-running processes.
The technical nature of this vulnerability stems from improper memory management within the sc_context_create function, where allocated memory is not properly freed or returned to the system after use. This creates a situation where memory fragments accumulate over time, leading to gradual memory consumption that can eventually cause system instability or denial of service conditions. The vulnerability is classified as a memory leak under CWE-401, which specifically addresses the failure to release or recycle memory resources. When the eidenv utility calls this function, it triggers the memory allocation process without subsequent deallocation, creating a persistent resource drain that can be exploited in resource-constrained environments or systems with high usage patterns.
The operational impact of this vulnerability extends beyond simple memory consumption issues, as it can significantly affect the stability and reliability of smart card applications that depend on OpenSC. Systems utilizing smart card authentication, digital signatures, or cryptographic operations may experience performance degradation or complete service failure when memory leaks accumulate over time. This vulnerability is particularly concerning in enterprise environments where smart card infrastructure is heavily utilized, as it can lead to unexpected system crashes or degraded performance during critical operations. The issue can be exploited by attackers who repeatedly invoke the affected function or maintain long-running processes that continuously consume memory resources, potentially leading to system compromise or service disruption.
Mitigation strategies for CVE-2019-6502 should prioritize immediate patching of affected OpenSC installations to version 0.19.1 or later, which contains the necessary memory management fixes. System administrators should implement monitoring solutions to track memory usage patterns and identify potential exploitation attempts. Additionally, the implementation of process isolation and resource limits can help contain the impact of memory leaks in case of exploitation. Organizations should also consider the ATT&CK framework's T1499 technique for resource exhaustion, which aligns with this vulnerability's potential for causing system instability through memory consumption. Regular security assessments and vulnerability scanning should be conducted to identify similar memory management issues within the broader smart card ecosystem and ensure comprehensive protection against similar threats.