CVE-2026-43133

Summary

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.

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxcc3ed80ae69f454c3d904af9f65394a540099723 < 10063e1251c1485034a018236080792ad083dcc5affected
LinuxLinuxcc3ed80ae69f454c3d904af9f65394a540099723 < c3b7015000988ba35ecd5648f4b2283960f00543affected
LinuxLinuxcc3ed80ae69f454c3d904af9f65394a540099723 < 3880e331b0b31d0d5d3702b124f6c93539cd478aaffected
LinuxLinuxcc3ed80ae69f454c3d904af9f65394a540099723 < fce2fd4a2ca05670a91015aacccf96a1c26268fdaffected
LinuxLinuxcc3ed80ae69f454c3d904af9f65394a540099723 < d464cf1ed900d47c85393d40b00017b6adfc2e6caffected
LinuxLinuxcc3ed80ae69f454c3d904af9f65394a540099723 < 0004ecb798b30e90d7ebfe74efae2d9423315a64affected
LinuxLinuxcc3ed80ae69f454c3d904af9f65394a540099723 < 127ccae2c185f62e6ecb4bf24f9cb307e9b9c619affected
LinuxLinux5.13affected
LinuxLinux0 < 5.13unaffected
LinuxLinux5.15.202 <= 5.15.*unaffected
LinuxLinux6.1.165 <= 6.1.*unaffected
LinuxLinux6.6.128 <= 6.6.*unaffected
LinuxLinux6.12.75 <= 6.12.*unaffected
LinuxLinux6.18.16 <= 6.18.*unaffected
LinuxLinux6.19.6 <= 6.19.*unaffected
LinuxLinux7.0 <= *unaffected

Weaknesses

ADP Enrichment

kernel: KVM: nSVM: Always use vmcb01 in VMLOAD/VMSAVE emulation

Additional References

References