CVE-2026-53278
MediumCVSS 5.5Exploitation Probability (EPSS)
Low risk1th percentile — higher than 1% of all known CVEs
Summary
In the Linux kernel ARM MPAM subsystem, a NULL pointer dereference vulnerability was found in __destroy_component_cfg(). The issue occurs when the function is called from mpam_disable() before the configuration array is allocated, leading to a system crash.
Risk Assessment
The risk involves a potential kernel panic when disabling the MPAM mechanism, which could disrupt system operations or hosted services.
Recommendation
Immediately update the Linux kernel to a version containing the fix that adds a check before freeing the configuration array and early return when the configuration is not allocated.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: arm_mpam: Check whether the config array is allocated before destroying it __destroy_component_cfg() is called to free the configuration array. It uses the embedded 'garbage' structure, which means the array has to be allocated. If __destroy_component_cfg() is called from mpam_disable() before the configuration was ever allocated, then a NULL pointer is dereferenced. Check for this case and return early if the configuration is not allocated. __destroy_component_cfg() also frees the mbwu_state as this is allocated by __allocate_component_cfg(). As the mbwu_state is allocated after comp->cfg is set, and is also under mpam_list_lock, only the first pointer needs checking.