# CVE-2024-53135: KVM: VMX: Bury Intel PT virtualization (guest/host mode) behind CONFIG_BROKEN

> A flaw in Linux kernel KVM Intel PT virtualization allows host instability or guest crashes due to missing validation, requiring CONFIG_BROKEN to be enabled.

- **Severity:** High 8.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 4 Dec 2024
- **Updated:** 15 Oct 2026
- **Also known as:** AZL-54141, AZL-54200, BELL-CVE-2024-53135, DEBIAN-CVE-2024-53135, GHSA-7gvv-gph6-2hpj, UBUNTU-CVE-2024-53135

## What is CVE-2024-53135?

CVE-2024-53135 is a high-severity denial of service vulnerability in Linux kernel, published on 4 Dec 2024. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

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

KVM: VMX: Bury Intel PT virtualization (guest/host mode) behind CONFIG_BROKEN

Hide KVM's pt_mode module param behind CONFIG_BROKEN, i.e. disable support
for virtualizing Intel PT via guest/host mode unless BROKEN=y.  There are
myriad bugs in the implementation, some of which are fatal to the guest,
and others which put the stability and health of the host at risk.

For guest fatalities, the most glaring issue is that KVM fails to ensure
tracing is disabled, and *stays* disabled prior to VM-Enter, which is
necessary as hardware disallows loading (the guest's) RTIT_CTL if tracing
is enabled (enforced via a VMX consistency check).  Per the SDM:

  If the logical processor is operating with Intel PT enabled (if
  IA32_RTIT_CTL.TraceEn = 1) at the time of VM entry, the "load
  IA32_RTIT_CTL" VM-entry control must be 0.

On the host side, KVM doesn't validate the guest CPUID configuration
provided by userspace, and even worse, uses the guest configuration to
decide what MSRs to save/load at VM-Enter and VM-Exit.  E.g. configuring
guest CPUID to enumerate more address ranges than are supported in hardware
will result in KVM trying to passthrough, save, and load non-existent MSRs,
which generates a variety of WARNs, ToPA ERRORs in the host, a potential
deadlock, etc.

## Which versions are affected by CVE-2024-53135?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-53135?

Apply the vendor's patch.

## Is CVE-2024-53135 being exploited?

There is no known exploitation of CVE-2024-53135 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-53135 and fix it if it is affected.

What it is: CVE-2024-53135 is a high-severity denial of service vulnerability in Linux kernel, published on 4 Dec 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2024-53135 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2024-53135/ (Markdown: https://insights.sbomify.com/CVE-2024-53135/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-53135
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-53135
- OSV: https://osv.dev/vulnerability/CVE-2024-53135

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-53135/
Summaries are generated and may contain mistakes; the official description above is the record.
