CVE-2026-64212 in Linux
Summary
by MITRE • 07/24/2026
In the Linux kernel, the following vulnerability has been resolved:
wifi: iwlwifi: mld: don't dereference a pointer before NULL checking it
In iwl_mld_remove_link, the link->fw_id is saved at the beginning of the function so we have it after we freed the link.
But the link pointer can be NULL, and is not checked when the fw_id is stored.
Fix it by simply freeing the link at the end of the function.
fFixes: 0e66a39f4f0e ("wifi: iwlwifi: fix potential use after free in iwl_mld_remove_link()")
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 07/24/2026
The vulnerability identified in the linux kernel's iwlwifi subsystem represents a classic use-after-free condition that could potentially lead to system instability or privilege escalation. This flaw exists within the iwl_mld_remove_link function where improper pointer validation creates an opportunity for malicious exploitation. The issue stems from the kernel's wireless driver implementation specifically designed for intel wireless hardware, making it relevant to a wide range of devices including laptops, desktops, and embedded systems that utilize intel wireless networking capabilities.
The technical flaw manifests when the function attempts to access link->fw_id without first validating whether the link pointer itself is NULL. This particular vulnerability falls under CWE-416 which specifically addresses use-after-free conditions in software development. The problematic code path occurs during the cleanup of wireless network links where the system tries to preserve firmware identification information before freeing memory structures. However, the function fails to check if the link parameter is valid before attempting to dereference it, creating a scenario where a NULL pointer dereference could occur.
When this vulnerability is exploited, the operational impact can be significant as it may lead to kernel crashes, system hangs, or potentially more severe consequences depending on how the exploitation occurs within the kernel's memory management subsystem. The function in question handles the removal of wireless network links which are fundamental components of the networking stack, making this a critical issue for system stability. The fix implemented by moving the link freeing operation to the end of the function ensures proper memory management and eliminates the race condition that previously existed between pointer validation and access operations.
The mitigation strategy directly addresses the root cause by ensuring that memory deallocation occurs only after all necessary operations are completed, thereby preventing any potential use-after-free scenarios. This approach aligns with established security practices for kernel development and follows the principle of proper resource management as outlined in various secure coding standards. The fix also demonstrates good defensive programming practices where developers should always validate pointers before dereferencing them, particularly in kernel space where such errors can have catastrophic consequences.
This vulnerability type is particularly concerning within the context of the ATT&CK framework's privilege escalation tactics, as memory corruption vulnerabilities in kernel space provide potential attack vectors for gaining elevated privileges. The fix maintains the intended functionality while eliminating the security risk through proper ordering of operations and ensuring that all resources are managed correctly throughout the function execution. The solution represents a minimal but effective change that preserves existing behavior while eliminating the dangerous pointer access pattern.