CVE-2026-93256

CVE Details

Release Date:	2026-09-24
Impact:	Low	What is this?

Description

In the Linux kernel, the following vulnerability has been resolved: arm64: hibernate: mask DAIF before restoring hibernated kernel The arm64 hibernate code manages the exception masking in an unsound way, leading to potential crashes and/or warnings during resume. When a hibernation image is saved in `swsusp_arch_suspend()`, all DAIF exceptions are masked (by virtue of `local_daif_save()`), and the suspended image is saved assuming that all DAIF exceptions will remain masked when the image is restored. When a hibernation image is resumed by `swsusp_arch_resume()`, only interrupts are masked (by virtue of `local_irq_disable()` in `resume_target_kernel()`). When pseudo-NMI is enabled the DAIF.IF bits will be clear, and regardless of pseudo-NMI the DAIF.DA bits will be clear. This means that there are two problems: (1) It is possible to take Debug, SError, or pseudo-NMI exceptions during the resume process. This is unsafe, as during the resume process both the old ane new kernels will tranisently be in an inconsistent state, and swsusp_arch_suspend_exit() won't retain an executable mapping of any exception vectors. Any exception taken here will be fatal and silent. (2) When re-entering the resumed kernel, some DAIF bits will be clear unexpectedly. This permits Debug, SError, or pseudo-NMI exceptions to be taken for a short period while the resumed kernel is not yet in a consistent state. This is detected by CONFIG_ARM64_DEBUG_PRIORITY_MASKING. Avoid these issues by masking all DAIF exceptions during resume.

See more information about CVE-2026-93256 from MITRE CVE dictionary and NIST NVD

NOTE: The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 metrics

Base Score:	4.1
Vector String:	CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H
Version:	3.1
Attack Vector:	Local
Attack Complexity:	High
Privileges Required:	High
User Interaction:	None
Scope:	Unchanged
Confidentiality Impact:	None
Integrity Impact:	None
Availability Impact:	High

Errata information

Platform	Errata	Release Date
Oracle Linux version 9 (kernel-uek)	ELSA-2026-500374	2026-10-07