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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.

Severity
Not scored
CVSS score
Not available
Vulnerability status
Awaiting Analysis
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-07-25 10:17:37.380000
Last modified
2026-11-03 18:15:39.353000
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"
            },
            {
              "version": "1b890ae474d19800a6be1696df7fb4d9a41676e4",
              "lessThan": "2fb80e962029000959f651665baa4838cc92eb99",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "2f4a4d63a193be6fd530d180bb13c3592052904c",
              "lessThan": "37f28bf8f14672dfa395994e41fd778a63f0bf5c",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "2f4a4d63a193be6fd530d180bb13c3592052904c",
              "lessThan": "f29dc6132d4968e39d8fa575d1a12e2c718ce57b",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "2f4a4d63a193be6fd530d180bb13c3592052904c",
              "lessThan": "dc066bd13c860bb27d6ace511210e18b8064c1d9",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "2f4a4d63a193be6fd530d180bb13c3592052904c",
              "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"
    },
    {
      "url": "https://git.kernel.org/stable/c/37f28bf8f14672dfa395994e41fd778a63f0bf5c",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b54c4632946ae42f2b39ed38abd909bbf78cbcc2",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/dc066bd13c860bb27d6ace511210e18b8064c1d9",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "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"
    }
  ]
}