CVE-2026-43401
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: cpufreq: intel_pstate: Fix NULL pointer dereference in update_cpu_qos_request() The update_cpu_qos_request() function attempts to initialize the 'freq' variable by dereferencing 'cpudata' before verifying if the 'policy' is valid. This issue occurs on systems booted with the "nosmt" parameter, where all_cpu_data[cpu] is NULL for the SMT sibling threads. As a result, any call to update_qos_requests() will result in a NULL pointer dereference as the code will attempt to access pstate.turbo_freq using the NULL cpudata pointer. Also, pstate.turbo_freq may be updated by intel_pstate_get_hwp_cap() after initializing the 'freq' variable, so it is better to defer the 'freq' until intel_pstate_get_hwp_cap() has been called. Fix this by deferring the 'freq' assignment until after the policy and driver_data have been validated. [ rjw: Added one paragraph to the changelog ]
Severity
MEDIUM
CVSS score
5.5
(v3.1)
Vulnerability status
Analyzed
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-05-08 15:16:51.543000
Last modified
2026-11-06 16:18:38.350000
View original CVE JSON
{
"id": "CVE-2026-43401",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-05-08T15:16:51.543",
"lastModified": "2026-11-06T16:18:38.350",
"vulnStatus": "Analyzed",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncpufreq: intel_pstate: Fix NULL pointer dereference in update_cpu_qos_request()\n\nThe update_cpu_qos_request() function attempts to initialize the 'freq'\nvariable by dereferencing 'cpudata' before verifying if the 'policy'\nis valid.\n\nThis issue occurs on systems booted with the \"nosmt\" parameter, where\nall_cpu_data[cpu] is NULL for the SMT sibling threads. As a result,\nany call to update_qos_requests() will result in a NULL pointer\ndereference as the code will attempt to access pstate.turbo_freq using\nthe NULL cpudata pointer.\n\nAlso, pstate.turbo_freq may be updated by intel_pstate_get_hwp_cap()\nafter initializing the 'freq' variable, so it is better to defer the\n'freq' until intel_pstate_get_hwp_cap() has been called.\n\nFix this by deferring the 'freq' assignment until after the policy and\ndriver_data have been validated.\n\n[ rjw: Added one paragraph to the changelog ]"
}
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"baseScore": 5.5,
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"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
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"id": "CVE-2026-43401",
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"weaknesses": [
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"source": "[email protected]",
"type": "Primary",
"description": [
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