CVE-2026-64286: Linux kernel · KVM: arm64: Clear __hyp_running_vcpu when flushing the pKVM hyp vCPU
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 8.2 High · fixed in 7.0.0-1012.12~24.04.1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 7% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 7.0.0-1012.12~24.04.1, 7.0.0-1011.11~24.04.1, 7.0.0-31.31~24.04.1 +7
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 25 Jul 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
Upgrade to a fixed release listed under Affected software.
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.
AI-suggested
A patch is available and has been released by the vendor. Users should update their Linux kernel packages to versions 7.0.0-31.31, 7.0.0-31.31.1, 7.0.0-1011.11, 7.0.0-1012.12, or later as appropriate for their distribution. After updating, a system reboot is required to apply the fixes. Due to an ABI change, recompilation and reinstallation of third-party kernel modules may be necessary. Follow the vendor's update instructions as detailed in the Ubuntu security notices USN-8726-1 and USN-8727-1.
Description
In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: Clear __hyp_running_vcpu when flushing the pKVM hyp vCPU flush_hyp_vcpu() copies the host vCPU context into the hyp's private vCPU on every run. ctxt_to_vcpu() expects a guest context to have a NULL __hyp_running_vcpu, which is only ever set on the host context, so that it resolves the vCPU via container_of(). While this is generally the case, flush_hyp_vcpu() copies the context verbatim and does not enforce this, so a value provided by the host is dereferenced at EL2 (host -> EL2). Fix by clearing __hyp_running_vcpu after the copy.
References
- nvd.nist.gov/vuln/detail/CVE-2026-64286 (opens in a new tab)
- git.kernel.org/stable/c/477145860dba4c30f0b4e36f02f4c5291c1c888b (opens in a new tab)
- git.kernel.org/stable/c/6bea2f8becdb20d34378493c3b77a9b9cf8c6cfa (opens in a new tab)
- git.kernel.org/stable/c/d4f4d61715d1061ba83b88196a3605662be30750 (opens in a new tab)
- git.kernel.org/stable/c/dfaef40d8a1533940fc1af788d70fce07362b4ce (opens in a new tab)
- git.kernel.org/stable/c/e8042f6e1d7befb2fb6b10a75918642bcd0acf9a (opens in a new tab)
- ubuntu.com/security/CVE-2026-64286 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-64286 (opens in a new tab)
- git.kernel.org/linus/e8042f6e1d7befb2fb6b10a75918642bcd0acf9a (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8727-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-1 (opens in a new tab)