CVE-2024-38609 in Linux
Summary
by MITRE • 06/19/2024
In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: connac: check for null before dereferencing
The wcid can be NULL. It should be checked for validity before dereferencing it to avoid crash.
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Analysis
by VulDB Data Team • 10/05/2025
The vulnerability identified as CVE-2024-38609 resides within the Linux kernel's wireless subsystem, specifically affecting the mt76 driver implementation for MediaTek WiFi chips. This issue represents a classic null pointer dereference flaw that occurs during wireless network connection handling. The vulnerability manifests in the connac wireless driver component which manages MediaTek MT76 series WiFi chipsets commonly found in various networking devices including routers and embedded systems. The flaw is particularly concerning as it affects the fundamental wireless connectivity operations within Linux-based systems.
The technical root cause of this vulnerability lies in improper null pointer validation within the wireless connection management code path. Specifically, the driver maintains a wireless connection identifier structure known as wcid that can legitimately become null during certain operational conditions such as connection teardown or error recovery scenarios. When the driver attempts to dereference this wcid pointer without first validating its null state, it results in an immediate system crash or kernel panic. This type of vulnerability falls under the CWE-476 category of NULL Pointer Dereference, which is a well-documented weakness in software security practices. The flaw demonstrates poor defensive programming where the code assumes pointer validity without proper validation checks.
The operational impact of CVE-2024-38609 extends beyond simple system crashes to potentially disrupt wireless connectivity services in affected devices. Systems utilizing MediaTek MT76-based WiFi hardware could experience unexpected kernel panics during normal wireless operations, particularly during connection establishment, reconnection attempts, or when handling network errors. This vulnerability affects a broad range of embedded devices, routers, and networking equipment that rely on Linux kernel wireless drivers for their network functionality. The crash condition could be exploited by malicious actors to cause denial of service attacks against wireless networks, potentially affecting network availability for legitimate users. From an attack surface perspective, this vulnerability aligns with ATT&CK technique T1499.004 for network denial of service, as it can be leveraged to disrupt wireless connectivity services.
Mitigation strategies for this vulnerability should focus on immediate kernel updates and patches provided by Linux kernel maintainers and device vendors. System administrators should prioritize applying the official kernel patches that implement proper null pointer validation before dereferencing the wcid structure. Additionally, monitoring systems should be configured to detect kernel panic events or wireless connectivity disruptions that may indicate exploitation attempts. Network administrators should consider implementing redundant wireless connectivity mechanisms and robust monitoring solutions to detect service disruptions. The fix typically involves adding a simple conditional check before pointer dereference operations, which aligns with standard secure coding practices recommended by both CWE guidelines and industry security frameworks. Organizations should also conduct vulnerability assessments to identify all devices utilizing affected MediaTek WiFi chipsets and ensure comprehensive patch management across their network infrastructure.