CVE-2026-43133
Vulnerability Summary
Timeline
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.
CVSS Metrics
- v4.0•LOW•Score: 2CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
- v3.1•HIGH•Score: 7.9CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:H
EPSS Trends
Current EPSS score: 0.13%• Percentile: 3%
Techniques & Countermeasures
- CWE-628•Function Call with Incorrectly Specified Arguments
The product calls a function, procedure, or routine with arguments that are not correctly specified, leading to always-incorrect behavior and resultant weaknesses.
Affected Systems
- debian•linux
< 6.1.170-1 | < 6.12.85-1 | < 6.19.6-1
- ubuntu•linux
< 5.15.0-186.196 | < 6.8.0-134.134 | all
- ubuntu•linux-allwinner-5.19
all
- ubuntu•linux-aws
< 5.15.0-1112.119 | < 6.8.0-1060.63 | all
- ubuntu•linux-aws-5.0
all
- ubuntu•linux-aws-5.11
all
- ubuntu•linux-aws-5.13
all
- ubuntu•linux-aws-5.15
< 5.15.0-1112.119~20.04.1
- ubuntu•linux-aws-5.19
all
- ubuntu•linux-aws-5.3
all
- ubuntu•linux-aws-5.8
all
- ubuntu•linux-aws-6.14
all
- ubuntu•linux-aws-6.17
all
- ubuntu•linux-aws-6.2
all
- ubuntu•linux-aws-6.5
all
- ubuntu•linux-aws-6.8
< 6.8.0-1060.63~22.04.1
- ubuntu•linux-aws-fips
all | < 5.15.0-1112.119+fips1 | < 6.8.0-1060.63+fips1
- ubuntu•linux-azure
all | < 5.15.0-1117.126 | < 6.8.0-1063.71 | all
- ubuntu•linux-azure-5.11
all
- ubuntu•linux-azure-5.13
all
- ubuntu•linux-azure-5.15
< 5.15.0-1117.126~20.04.1
- ubuntu•linux-azure-5.19
all
- ubuntu•linux-azure-5.3
all
- ubuntu•linux-azure-5.8
all
- ubuntu•linux-azure-6.11
all
- ubuntu•linux-azure-6.14
all
- ubuntu•linux-azure-6.17
all
- ubuntu•linux-azure-6.2
all
- ubuntu•linux-azure-6.5
all
- ubuntu•linux-azure-6.8
< 6.8.0-1063.71~22.04.1
- ubuntu•linux-azure-edge
all
- ubuntu•linux-azure-fde
all | < 5.15.0-1117.126 | < 6.8.0-1062.69 | all | all
- ubuntu•linux-azure-fde-5.15
< 5.15.0-1117.126~20.04.2
- ubuntu•linux-azure-fde-5.19
all
- ubuntu•linux-azure-fde-6.14
all
- ubuntu•linux-azure-fde-6.2
all
- ubuntu•linux-azure-fde-6.8
< 6.8.0-1062.69~22.04.1
- ubuntu•linux-azure-fde-7.0
all
- ubuntu•linux-azure-fips
all | < 5.15.0-1117.126+fips1 | < 6.8.0-1062.69+fips1
- ubuntu•linux-azure-nvidia
all
- ubuntu•linux-azure-nvidia-6.14
all
- ubuntu•linux-bluefield
all | < 5.15.0-1096.98 | < 6.8.0-1026.30
- ubuntu•linux-fips
all | < 5.15.0-186.196+fips1 | < 6.8.0-134.134+fips1
- ubuntu•linux-gcp
all | < 5.15.0-1112.122 | < 6.8.0-1063.69 | all
- ubuntu•linux-gcp-5.11
all
- ubuntu•linux-gcp-5.13
all
- ubuntu•linux-gcp-5.15
all | < 5.15.0-1112.122~20.04.1
- ubuntu•linux-gcp-5.19
all
- ubuntu•linux-gcp-5.3
all
- ubuntu•linux-gcp-5.8
all
Showing first 50 affected entries in server-rendered view.
References (42)
- https://git.kernel.org/stable/c/0004ecb798b30e90d7ebfe74efae2d9423315a64
- https://git.kernel.org/stable/c/10063e1251c1485034a018236080792ad083dcc5
- https://git.kernel.org/stable/c/127ccae2c185f62e6ecb4bf24f9cb307e9b9c619
- https://git.kernel.org/stable/c/3880e331b0b31d0d5d3702b124f6c93539cd478a
- https://git.kernel.org/stable/c/c3b7015000988ba35ecd5648f4b2283960f00543
- https://git.kernel.org/stable/c/d464cf1ed900d47c85393d40b00017b6adfc2e6c
- https://git.kernel.org/stable/c/fce2fd4a2ca05670a91015aacccf96a1c26268fd
- https://access.redhat.com/security/cve/CVE-2026-43133
- https://bugzilla.redhat.com/show_bug.cgi?id=2467065
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43133.json
- https://ubuntu.com/security/CVE-2026-43133
- https://www.cve.org/CVERecord?id=CVE-2026-43133
- https://git.kernel.org/linus/127ccae2c185f62e6ecb4bf24f9cb307e9b9c619
- https://ubuntu.com/security/notices/USN-8492-1
- https://ubuntu.com/security/notices/USN-8492-2
- https://ubuntu.com/security/notices/USN-8497-1
- https://ubuntu.com/security/notices/USN-8498-1
- https://ubuntu.com/security/notices/USN-8499-1
- https://ubuntu.com/security/notices/USN-8492-3
- https://ubuntu.com/security/notices/USN-8492-4
- https://ubuntu.com/security/notices/USN-8492-5
- https://ubuntu.com/security/notices/USN-8575-1
- https://ubuntu.com/security/notices/USN-8576-1
- https://ubuntu.com/security/notices/USN-8575-2
- https://ubuntu.com/security/notices/USN-8576-2
- https://ubuntu.com/security/notices/USN-8606-1
- https://ubuntu.com/security/notices/USN-8607-1
- https://ubuntu.com/security/notices/USN-8609-1
- https://ubuntu.com/security/notices/USN-8575-3
- https://ubuntu.com/security/notices/USN-8610-1
- https://ubuntu.com/security/notices/USN-8619-1
- https://ubuntu.com/security/notices/USN-8620-1
- https://ubuntu.com/security/notices/USN-8620-2
- https://ubuntu.com/security/notices/USN-8620-3
- https://ubuntu.com/security/notices/USN-8620-4
- https://security-tracker.debian.org/tracker/CVE-2026-43133
- https://ubuntu.com/security/notices/USN-8668-1
- https://access.redhat.com/errata/RHSA-2026:65334
- https://access.redhat.com/errata/RHSA-2026:66180
- https://access.redhat.com/errata/RHSA-2026:66357
- https://access.redhat.com/errata/RHSA-2026:67468
- https://access.redhat.com/errata/RHSA-2026:67469