CVE-2026-53318 in Linux
Summary
by MITRE • 06/26/2026
In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: mt7925: prevent NULL pointer dereference in mt7925_tx_check_aggr()
Move the NULL check for 'sta' before dereferencing it to prevent a possible crash.
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Analysis
by VulDB Data Team • 06/26/2026
The vulnerability identified in the Linux kernel affects the mt7925 wireless driver component within the mt76 subsystem, specifically in the mt7925_tx_check_aggr() function. This represents a classic null pointer dereference flaw that could lead to system instability and potential denial of service conditions. The issue stems from improper validation of pointer references before memory access operations, creating an exploitable condition that adversaries could leverage to disrupt wireless networking functionality.
The technical flaw manifests when the driver processes transmission aggregation checks for wireless frames without first validating whether the station (sta) pointer is properly initialized. According to common weakness enumeration standards, this vulnerability maps directly to CWE-476 which describes NULL Pointer Dereference conditions. The function mt7925_tx_check_aggr() attempts to access member variables or functions of the sta structure without ensuring that the pointer itself points to valid memory location, creating a scenario where kernel execution flow could terminate abruptly when encountering a null reference.
Operational impact of this vulnerability extends beyond simple system crashes to encompass broader network service disruption. When exploited, the NULL pointer dereference can cause the wireless subsystem to become unresponsive, leading to complete loss of wireless connectivity for affected devices. This affects systems running Linux kernels with mt7925 hardware support including various laptops, desktops, and embedded devices utilizing Mediatek MT7925 chipset. The vulnerability is particularly concerning in enterprise environments where wireless infrastructure reliability is critical, as it could enable denial of service attacks against wireless services or cause unexpected system reboots during active network operations.
The mitigation strategy involves implementing proper pointer validation before any dereference operations within the mt7925_tx_check_aggr() function. This aligns with established security practices from the ATT&CK framework under the technique T1499.004 for Network Denial of Service and T1566.002 for Pre-Attack Phases, as proper input validation serves as a fundamental defense mechanism. The fix requires moving existing NULL checks for the 'sta' parameter to occur before any pointer dereferencing operations, ensuring that the driver gracefully handles cases where station information may not be available during transmission processing. This remediation approach follows standard kernel security best practices and represents a minimal code change that effectively prevents the crash condition while maintaining full wireless functionality.
The vulnerability demonstrates how seemingly minor oversight in kernel driver development can create significant stability issues. It highlights the importance of defensive programming practices in kernel space where memory access errors can directly impact system integrity. Modern kernel security frameworks emphasize early validation and proper error handling as primary defense mechanisms against such flaws, making this fix representative of broader security engineering principles that should be applied across all kernel subsystems to prevent similar conditions from manifesting in other components.