CVE-2024-53135: In the Linux kernel, the following vulnerability has been resolved: KVM: VMX: Bury Intel PT virtualization (guest/host mode) behind CONFIG

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 p

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

Description from the National Vulnerability Database, published by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

What it means for a small business

Linux is on the computers, phones or browsers your team uses every day. Turn on automatic updates and restart: most of these fixes only take effect after a restart.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 0.24%, higher than 15% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored October 29, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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