CVE-2026-98716 PUBLISHED

KVM: SVM: Use the active VMCB's MSR bitmap when checking if MSR is intercepted

Assigner: Linux
Reserved: 25.09.2026 Published: 18.10.2026 Updated: 18.10.2026

In the Linux kernel, the following vulnerability has been resolved:

KVM: SVM: Use the active VMCB's MSR bitmap when checking if MSR is intercepted

Use the MSR permission bitmap of the active VMCB instead of assuming that KVM is always using vmcb02's bitmap when L2 is active, as KVM uses msrpm02 if and only if L1 wants to intercept MSR accesses, i.e. if and only if KVM needs to merge msprm01 with msrpm12.

Don't bother tracking the virtual address of the bitmap that's being used, as __va() is cheap on x86, and caching the virtual address would introduce yet another source of potentially stale information.

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from b2ac58f90540e39324e7a29a7ad471407ae0bf48 to 74836ae4785b9754bb36d0b18fcc1dec4e5e98d2 (excl.)
  • affected from b2ac58f90540e39324e7a29a7ad471407ae0bf48 to 318ef696fa3c712e46bb62a1a828c3cd62f390c3 (excl.)
  • affected from b2ac58f90540e39324e7a29a7ad471407ae0bf48 to 55865b3ae03705aa39198783b9cb1f8b96eb44e4 (excl.)
  • affected from b2ac58f90540e39324e7a29a7ad471407ae0bf48 to 9e06bbb9ade7cdf28d4a3b5b14e5812881c8df85 (excl.)
  • Version f54d0bb8487d2f016fbc4f0e38ef9098f8eb8bd4 is affected
  • Version 89be8950bab799ddb9cc3777345e3c21bcb32dba is affected
  • affected from 3.16.57 to 3.17 (excl.)
  • affected from 4.4.168 to 4.5 (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 4.16 is affected
  • unaffected from 0 to 4.16 (excl.)
  • unaffected from 6.12.113 to 6.12.* (incl.)
  • unaffected from 6.18.56 to 6.18.* (incl.)
  • unaffected from 7.2.10 to 7.2.* (incl.)
  • unaffected from 7.3-rc6 to * (incl.)

References