CVE-2026-64512
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: ACPI: CPPC: Suppress UBSAN warning caused by field misuse The definition of reg->access_width changes depending on the reg->space_id type. Type ACPI_ADR_SPACE_PLATFORM_COMM uses access_width to indicate the PCC region, which can result in a UBSAN if the value is greater than 4. For example: UBSAN: shift-out-of-bounds in drivers/acpi/cppc_acpi.c:1090:9 shift exponent 32 is too large for 32-bit type 'int' CPU: 61 UID: 0 PID: 1220 Comm: (udev-worker) Not tainted 7.0.10-201.fc44.aarch64 #1 PREEMPT(lazy) Hardware name: To be filled by O.E.M. Call trace: ...(trimming) ubsan_epilogue+0x10/0x48 __ubsan_handle_shift_out_of_bounds+0xdc/0x1e0 cpc_write+0x4d0/0x670 cppc_set_perf+0x18c/0x490 cppc_cpufreq_cpu_init+0x1c8/0x380 [cppc_cpufreq] ... (trimming) Lets fix this by validating the region type, as well as whether access_width has a value. Then since we are returning bit_width directly for ACPI_ADR_SPACE_PLATFORM_COMM, drop the code correcting the size.
View original CVE JSON
{
"id": "CVE-2026-64512",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-07-25T10:17:37.380",
"lastModified": "2026-11-03T18:15:39.353",
"vulnStatus": "Awaiting Analysis",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nACPI: CPPC: Suppress UBSAN warning caused by field misuse\n\nThe definition of reg->access_width changes depending on the\nreg->space_id type. Type ACPI_ADR_SPACE_PLATFORM_COMM uses\naccess_width to indicate the PCC region, which can result in a UBSAN\nif the value is greater than 4.\n\nFor example:\n\n UBSAN: shift-out-of-bounds in drivers/acpi/cppc_acpi.c:1090:9\n shift exponent 32 is too large for 32-bit type 'int'\n CPU: 61 UID: 0 PID: 1220 Comm: (udev-worker) Not tainted 7.0.10-201.fc44.aarch64 #1 PREEMPT(lazy)\n Hardware name: To be filled by O.E.M.\n Call trace:\n ...(trimming)\n ubsan_epilogue+0x10/0x48\n __ubsan_handle_shift_out_of_bounds+0xdc/0x1e0\n cpc_write+0x4d0/0x670\n cppc_set_perf+0x18c/0x490\n cppc_cpufreq_cpu_init+0x1c8/0x380 [cppc_cpufreq]\n ... (trimming)\n\nLets fix this by validating the region type, as well as whether\naccess_width has a value. Then since we are returning bit_width\ndirectly for ACPI_ADR_SPACE_PLATFORM_COMM, drop the code correcting\nthe size."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"drivers/acpi/cppc_acpi.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "4949affd5288b867cdf115f5b08d6166b2027f87",
"lessThan": "b54c4632946ae42f2b39ed38abd909bbf78cbcc2",
"versionType": "git",
"status": "affected"
},
{
"version": "01fc53be672acae37e611c80cc0b4f3939584de3",
"lessThan": "e904596ba6dd108534ffa15e3e46b2fe245145e2",
"versionType": "git",
"status": "affected"
},
{
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"lessThan": "2fb80e962029000959f651665baa4838cc92eb99",
"versionType": "git",
"status": "affected"
},
{
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"versionType": "git",
"status": "affected"
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{
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"versionType": "git",
"status": "affected"
},
{
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"status": "affected"
},
{
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"lessThan": "1b1acf2dada0cc3931bb2cb9ff8832edfbee46a1",
"versionType": "git",
"status": "affected"
},
{
"version": "6cb6b12b78dcd8867a3fdbb1b6d0ed1df2b208d1",
"versionType": "git",
"status": "affected"
},
{
"version": "5.15.154",
"lessThan": "5.15.155",
"versionType": "semver",
"status": "affected"
},
{
"version": "6.1.90",
"lessThan": "6.1.178",
"versionType": "semver",
"status": "affected"
},
{
"version": "6.6.30",
"lessThan": "6.6.145",
"versionType": "semver",
"status": "affected"
},
{
"version": "6.8.9",
"lessThan": "6.9",
"versionType": "semver",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"drivers/acpi/cppc_acpi.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "6.9",
"status": "affected"
},
{
"version": "0",
"lessThan": "6.9",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.15.155",
"lessThanOrEqual": "5.15.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.1.178",
"lessThanOrEqual": "6.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.6.145",
"lessThanOrEqual": "6.6.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.12.96",
"lessThanOrEqual": "6.12.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.18.39",
"lessThanOrEqual": "6.18.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.1.4",
"lessThanOrEqual": "7.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.2",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {},
"references": [
{
"url": "https://git.kernel.org/stable/c/1b1acf2dada0cc3931bb2cb9ff8832edfbee46a1",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/2fb80e962029000959f651665baa4838cc92eb99",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
"url": "https://git.kernel.org/stable/c/e904596ba6dd108534ffa15e3e46b2fe245145e2",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/f29dc6132d4968e39d8fa575d1a12e2c718ce57b",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
]
}