CVE-2026-64512
ACPI: CPPC: Suppress UBSAN warning caused by field misuse
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.
INFO
Published Date :
July 25, 2026, 10:17 a.m.
Last Modified :
July 25, 2026, 10:17 a.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products
The following products are affected by CVE-2026-64512
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
Solution
- Validate region type and access_width.
- Drop incorrect size correction code.
- Apply kernel patches.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-64512.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-64512 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-64512
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-64512 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-64512 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jul. 25, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', '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'}], 'programFiles': ['drivers/acpi/cppc_acpi.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.9'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.9', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.15.155', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.178', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.145', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.96', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.39', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.4', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['drivers/acpi/cppc_acpi.c'], 'defaultStatus': 'affected'}] Added 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. Added Reference https://git.kernel.org/stable/c/1b1acf2dada0cc3931bb2cb9ff8832edfbee46a1 Added Reference https://git.kernel.org/stable/c/2fb80e962029000959f651665baa4838cc92eb99 Added Reference https://git.kernel.org/stable/c/37f28bf8f14672dfa395994e41fd778a63f0bf5c Added Reference https://git.kernel.org/stable/c/b54c4632946ae42f2b39ed38abd909bbf78cbcc2 Added Reference https://git.kernel.org/stable/c/dc066bd13c860bb27d6ace511210e18b8064c1d9 Added Reference https://git.kernel.org/stable/c/e904596ba6dd108534ffa15e3e46b2fe245145e2 Added Reference https://git.kernel.org/stable/c/f29dc6132d4968e39d8fa575d1a12e2c718ce57b