CVE-2024-44948
MediumCVSS 5.5Exploitation Probability (EPSS)
Low risk14th percentile - higher than 14% of all known CVEs
Summary
In the Linux kernel x86/mtrr module, mtrr_save_state() did not check the fixed MTRR capability bit before accessing the MSRs. On CPUs without this capability, this causes a #GP exception and a WARN_ON().
Risk Assessment
May cause exceptions and kernel warnings on some processors, potentially leading to system instability.
Recommendation
Update the Linux kernel to a version containing the fix that adds the fixed MTRR capability check.
Other vulnerabilities in Linux kernel
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- CVE-2026-99258Unknown
In the Linux kernel, hv_apicid_to_vp_index() uses per-CPU hypercall input and output pages. In an SEV-SNP CoCo VM without a paravisor the output page is not allocated, so the hypervisor stores the resulting VP index into memory not allocated by the guest. The fix uses the input page for both input and output.
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In the Linux kernel, the shared GPIO mechanism based on platform lookup tables requires an associated struct device. An fwnode-based lookup with no associated device currently causes a NULL-pointer dereference. The fix adds a check that lets the kernel gracefully handle this situation with an error.
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- CVE-2026-99250Unknown
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- CVE-2026-99249Unknown
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- CVE-2026-99247Unknown
In the Linux kernel, if trace buffer allocation fails during early boot, tracing_disabled remains set and the global trace array events list stays uninitialized. tracer_init_tracefs_work_func() runs asynchronously without checking this state and calls event_trace_init() and init_tracer_tracefs(), leading to a NULL pointer dereference Oops during boot. The fix checks tracing_disabled at the start of the work function.
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In the Linux kernel power supply subsystem, a use-after-free vulnerability exists. If a power supply is unregistered while its external_power_changed() callback is still running, the driver may free data that the callback is still accessing, leading to a kernel crash (NULL pointer dereference).
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: x86/mtrr: Check if fixed MTRRs exist before saving them MTRRs have an obsolete fixed variant for fine grained caching control of the 640K-1MB region that uses separate MSRs. This fixed variant has a separate capability bit in the MTRR capability MSR. So far all x86 CPUs which support MTRR have this separate bit set, so it went unnoticed that mtrr_save_state() does not check the capability bit before accessing the fixed MTRR MSRs. Though on a CPU that does not support the fixed MTRR capability this results in a #GP. The #GP itself is harmless because the RDMSR fault is handled gracefully, but results in a WARN_ON(). Add the missing capability check to prevent this.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

