The Linux kernel on ARM64 architectures incorrectly handles DAIF exception masking during the hibernate resume path. When the system suspends, all DAIF bits are fully masked, but the resume routine only masks interrupts, leaving Debug, SError, and pseudo‑NMI exceptions unmasked while the kernel is in an inconsistent state. If any of these exceptions occur, the kernel crashes silently, which can cause the system to reboot or hang. The underlying weakness is an internal fault caused by improper exception masking across suspend boundaries, compromising the integrity of the kernel state.

All Linux kernels running on ARM64 devices that use the standard swsusp suspend/resume mechanism are affected. This includes every kernel build that has not incorporated the patch that masks all DAIF bits during resume. The issue is not tied to a particular release version, so any kernel version prior to the fix is potentially vulnerable.

The flaw does not rely on any user‑supplied input; it is triggered internally during the resume operation. An attacker would need to cause the system to resume from a hibernation image that could be corrupted or maliciously crafted, which is not documented as an external attack vector. The EPSS score is not available and the vulnerability is not listed in CISA's KEV catalog, suggesting no known public exploitation. Nonetheless, the impact—a kernel crash that disrupts availability—is high, and the risk can be considered moderate to high for environments that rely on hibernation.