CVE-2026-64183
efi: Allocate runtime workqueue before ACPI init
Description
In the Linux kernel, the following vulnerability has been resolved: efi: Allocate runtime workqueue before ACPI init Since commit 5894cf571e14 ("acpi/prmt: Use EFI runtime sandbox to invoke PRM handlers") ACPI PRM calls are delegated to a workqueue which runs in a kernel thread, making it easier to detect and mitigate faulting memory accesses performed by the firmware. Rafael reports that such PRM accesses may occur before efisubsys_init() executes, which is where the workqueue is allocated, leading to NULL pointer dereferences. Since acpi_init() [which triggers the early PRM accesses] executes as a subsys_initcall() as well, and has its own dependencies that may be sensitive to initcall ordering, deferring acpi_init() is not an option. So instead, split off the workqueue allocation into its own postcore initcall, as this is the only missing piece to allow EFI runtime calls to be made. This ensures that EFI runtime call (including PRM calls) are accessible to all code running at subsys_initcall() level.
INFO
Published Date :
July 19, 2026, 4:18 p.m.
Last Modified :
July 19, 2026, 4:18 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products
The following products are affected by CVE-2026-64183
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
- Ensure workqueue allocation occurs before ACPI initialization.
- Update the Linux kernel to include the fix.
- Defer ACPI initialization if necessary.
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-2026-64183.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-64183 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-2026-64183
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-2026-64183 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-64183 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.
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New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jul. 19, 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': '5894cf571e14fb393a4d0a82538de032127b9d8b', 'lessThan': '29cd94e678fcb3c4fd0f359deeac6d61334323fc', 'versionType': 'git'}, {'status': 'affected', 'version': '5894cf571e14fb393a4d0a82538de032127b9d8b', 'lessThan': '6996e954ae830f5b793ba6cf449885ca519dbdd2', 'versionType': 'git'}, {'status': 'affected', 'version': '5894cf571e14fb393a4d0a82538de032127b9d8b', 'lessThan': 'c32a1fbe0f9a48453a552bb315cc4f1e7a74084e', 'versionType': 'git'}, {'status': 'affected', 'version': '5894cf571e14fb393a4d0a82538de032127b9d8b', 'lessThan': 'e871549f7894ad4114b3dd53f241aa25a268ba8b', 'versionType': 'git'}, {'status': 'affected', 'version': '5894cf571e14fb393a4d0a82538de032127b9d8b', 'lessThan': '13c6da02e767152c9ac4330962247a5e47011035', 'versionType': 'git'}], 'programFiles': ['drivers/firmware/efi/efi.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.6'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.6', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.6.142', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.92', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.34', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.0.11', 'versionType': 'semver', 'lessThanOrEqual': '7.0.*'}, {'status': 'unaffected', 'version': '7.1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['drivers/firmware/efi/efi.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: efi: Allocate runtime workqueue before ACPI init Since commit 5894cf571e14 ("acpi/prmt: Use EFI runtime sandbox to invoke PRM handlers") ACPI PRM calls are delegated to a workqueue which runs in a kernel thread, making it easier to detect and mitigate faulting memory accesses performed by the firmware. Rafael reports that such PRM accesses may occur before efisubsys_init() executes, which is where the workqueue is allocated, leading to NULL pointer dereferences. Since acpi_init() [which triggers the early PRM accesses] executes as a subsys_initcall() as well, and has its own dependencies that may be sensitive to initcall ordering, deferring acpi_init() is not an option. So instead, split off the workqueue allocation into its own postcore initcall, as this is the only missing piece to allow EFI runtime calls to be made. This ensures that EFI runtime call (including PRM calls) are accessible to all code running at subsys_initcall() level. Added Reference https://git.kernel.org/stable/c/13c6da02e767152c9ac4330962247a5e47011035 Added Reference https://git.kernel.org/stable/c/29cd94e678fcb3c4fd0f359deeac6d61334323fc Added Reference https://git.kernel.org/stable/c/6996e954ae830f5b793ba6cf449885ca519dbdd2 Added Reference https://git.kernel.org/stable/c/c32a1fbe0f9a48453a552bb315cc4f1e7a74084e Added Reference https://git.kernel.org/stable/c/e871549f7894ad4114b3dd53f241aa25a268ba8b