Vulnerability in Linux Kernel Affects Arm64 Hibernation Process

CVE-2026-93256

What is CVE-2026-93256?

The arm64 hibernation code within the Linux kernel has a flaw in exception masking that can lead to system instability during the resume process. When a hibernation image is saved, it incorrectly assumes that all exceptions will remain masked upon restoration. This can cause fatal errors due to the potential for Debug, SError, or pseudo-NMI exceptions to occur during a critical time when both old and new kernel states are simultaneously present. Mitigating this vulnerability involves ensuring all DAIF exceptions are properly masked during resume operations to avoid transient inconsistent states that could lead to crashes or silent failures.

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