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CVE-2026-43133

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: KVM: nSVM: Always use vmcb01 in VMLOAD/VMSAVE emulation Commit cc3ed80ae69f ("KVM: nSVM: always use vmcb01 to for vmsave/vmload of guest state") made KVM always use vmcb01 for the fields controlled by VMSAVE/VMLOAD, but it missed updating the VMLOAD/VMSAVE emulation code to always use vmcb01. As a result, if VMSAVE/VMLOAD is executed by an L2 guest and is not intercepted by L1, KVM will mistakenly use vmcb02. Always use vmcb01 instead of the current VMCB.

Severity
HIGH
CVSS score
7.9 (v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-05-06 12:16:30.480000
Last modified
2026-10-19 20:18:07.837000
View original CVE JSON 
{
  "id": "CVE-2026-43133",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-05-06T12:16:30.480",
  "lastModified": "2026-10-19T20:18:07.837",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: nSVM: Always use vmcb01 in VMLOAD/VMSAVE emulation\n\nCommit cc3ed80ae69f (\"KVM: nSVM: always use vmcb01 to for vmsave/vmload\nof guest state\") made KVM always use vmcb01 for the fields controlled by\nVMSAVE/VMLOAD, but it missed updating the VMLOAD/VMSAVE emulation code\nto always use vmcb01.\n\nAs a result, if VMSAVE/VMLOAD is executed by an L2 guest and is not\nintercepted by L1, KVM will mistakenly use vmcb02. Always use vmcb01\ninstead of the current VMCB."
    }
  ],
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