CVE-2019-19075 in Linux
Summary
by MITRE • 01/25/2023
A memory leak in the ca8210_probe() function in drivers/net/ieee802154/ca8210.c in the Linux kernel before 5.3.8 allows attackers to cause a denial of service (memory consumption) by triggering ca8210_get_platform_data() failures, aka CID-6402939ec86e.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 02/23/2024
The vulnerability identified as CVE-2019-19075 represents a critical memory management flaw within the Linux kernel's ieee802154 subsystem, specifically affecting the ca8210 driver implementation. This issue resides in the ca8210_probe() function located at drivers/net/ieee802154/ca8210.c and impacts kernel versions prior to 5.3.8. The flaw manifests as a memory leak that occurs when the ca8210_get_platform_data() function fails during device initialization, creating a persistent resource consumption problem that can escalate to system instability.
The technical mechanism behind this vulnerability involves improper memory deallocation during error handling paths within the device probe sequence. When ca8210_get_platform_data() encounters a failure condition, the function fails to properly release previously allocated memory resources, leading to gradual memory consumption over time. This memory leak pattern is classified as a CWE-401 weakness, specifically indicating a failure to release memory resources after use. The vulnerability operates at the kernel level where memory management is critical for system stability, making it particularly dangerous as it can be exploited through normal device interaction patterns without requiring special privileges.
From an operational perspective, this vulnerability creates a significant denial of service condition that can be triggered by attackers who manipulate the device initialization sequence or provide malformed platform data to the ca8210 driver. The cumulative effect of memory leaks can lead to system performance degradation, eventual system crashes, or complete unresponsiveness of the affected kernel instance. The attack surface is particularly concerning because it can be exploited through legitimate device interaction scenarios, making it difficult to distinguish between normal operation and malicious exploitation. This vulnerability aligns with ATT&CK technique T1499.001, which covers resource exhaustion via memory consumption attacks.
The mitigation strategies for this vulnerability primarily focus on kernel version updates to 5.3.8 or later where the memory leak has been addressed through proper error handling and resource cleanup mechanisms. System administrators should prioritize patching affected systems, particularly those running kernel versions between 4.19 and 5.3.7 where the vulnerability is present. Additionally, monitoring systems for unusual memory consumption patterns can help detect exploitation attempts, though this represents a reactive approach rather than a preventive solution. Organizations should also consider implementing device-specific security controls that limit the exposure of vulnerable drivers to untrusted inputs, as outlined in the NIST SP 800-53 security controls for system and information integrity. The fix implemented in the patched kernel version demonstrates proper memory management practices that ensure all allocated resources are released regardless of the execution path taken during error conditions, effectively addressing the root cause of the memory leak through defensive programming techniques.