CVE-2026-93256: Linux kernel · arm64: hibernate: mask DAIF before restoring hibernated kernel
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 26 Oct 2026, 14:05 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 11% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Exploitation evidence
Disclosed: evidence found.
CVE published 24 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
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.
References
- ubuntu.com/security/CVE-2026-93256 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-93256 (opens in a new tab)
- git.kernel.org/stable/c/d736ace2c491623c9ab5e73744085e93e9ae3ebe (opens in a new tab)
- git.kernel.org/stable/c/716c41bd476334afb943308be9ff2142e34461b7 (opens in a new tab)
- git.kernel.org/stable/c/012823494e20c3cce622982ebd3fd6971be39ad2 (opens in a new tab)
- git.kernel.org/stable/c/684bde100117931f4c51c644a95f42f2dab041bc (opens in a new tab)
- git.kernel.org/stable/c/c9c671e9ab87b639720db8f7f8648bdf0f3bc8ec (opens in a new tab)
- git.kernel.org/stable/c/5370853041a3cb53a125b77528586278f64b378b (opens in a new tab)
- git.kernel.org/stable/c/099ad3edcef1d955d9f5d6aab16ae78ecdfd4cda (opens in a new tab)
- git.kernel.org/stable/c/290c5b0c9fc0c61fb1c41421ed2394f955206ea0 (opens in a new tab)
- msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-93256.json (opens in a new tab)
- support.microsoft.com/lifecycle (opens in a new tab)
- first.org/cvss (opens in a new tab)