CVE-2023-54053: 
Linux Kernel vulnerability analysis and mitigation

CVE-2023-54053 is a NULL pointer dereference vulnerability in the Linux kernel's iwlwifi PCIe Wi-Fi driver. The flaw occurs when iwl_pci_probe() fails and frees the trans structure, after which iwl_pci_remove() is subsequently called and attempts to access the already-freed pointer, causing a kernel crash. The vulnerability affects the Linux kernel across multiple stable branches, with fixes backported to versions 5.4.244, 5.10.181, 5.15.113, 6.1.30, 6.3.4, and 6.4. It was published on December 24, 2025, and has no CVSS base score assigned at this time (Feedly, ENISA EUVD).

The root cause is a use-after-free / NULL pointer dereference (CWE-476) in the iwlwifi PCIe driver within the Linux kernel. When iwl_pci_probe() encounters an error (e.g., failing to identify a valid RF ID for the detected hardware), it frees the trans structure and returns an error code. However, the PCI subsystem subsequently calls iwl_pci_remove() during driver cleanup, which dereferences the now-freed trans pointer at offset 0x28, triggering a kernel NULL pointer dereference. The crash manifests with a BUG: kernel NULL pointer dereference at RIP: 0010:iwl_pci_remove+0x12/0x30 [iwlwifi], propagating through pci_device_remove, device_release_driver_internal, and driver_detach (Feedly).

Successful triggering of this vulnerability causes a kernel panic (system crash), resulting in a denial of service on the affected host. The impact is limited to availability — confidentiality and integrity are not directly affected. The vulnerability is local in nature, typically triggered during hardware initialization or driver module removal on systems with affected Intel Wi-Fi hardware (Feedly, ENISA EUVD).

The Linux kernel maintainers have released patches across multiple stable branches. Affected users should update to the following fixed versions or later: 5.4.244, 5.10.181, 5.15.113, 6.1.30, 6.3.4, or 6.4. The fix ensures that iwl_pci_remove() safely handles the case where trans is NULL or already freed after a failed probe. Linux distribution vendors (e.g., Red Hat, Ubuntu, SUSE) are expected to backport these fixes into their respective kernel packages; users should apply available distribution security updates promptly (Feedly, ENISA EUVD).