{"cve":"CVE-2026-64183","nvd":{"published":"2026-07-19T16:18:00.703","modified":"2026-08-11T20:05:55.917","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nefi: Allocate runtime workqueue before ACPI init\n\nSince commit\n\n  5894cf571e14 (\"acpi/prmt: Use EFI runtime sandbox to invoke PRM handlers\")\n\nACPI PRM calls are delegated to a workqueue which runs in a kernel\nthread, making it easier to detect and mitigate faulting memory accesses\nperformed by the firmware.\n\nRafael reports that such PRM accesses may occur before efisubsys_init()\nexecutes, which is where the workqueue is allocated, leading to NULL\npointer dereferences. Since acpi_init() [which triggers the early PRM\naccesses] executes as a subsys_initcall() as well, and has its own\ndependencies that may be sensitive to initcall ordering, deferring\nacpi_init() is not an option.\n\nSo instead, split off the workqueue allocation into its own postcore\ninitcall, as this is the only missing piece to allow EFI runtime calls\nto be made. This ensures that EFI runtime call (including PRM calls) are\naccessible to all code running at subsys_initcall() level.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-476"],"references":["https://git.kernel.org/stable/c/13c6da02e767152c9ac4330962247a5e47011035","https://git.kernel.org/stable/c/29cd94e678fcb3c4fd0f359deeac6d61334323fc","https://git.kernel.org/stable/c/6996e954ae830f5b793ba6cf449885ca519dbdd2","https://git.kernel.org/stable/c/c32a1fbe0f9a48453a552bb315cc4f1e7a74084e","https://git.kernel.org/stable/c/e871549f7894ad4114b3dd53f241aa25a268ba8b"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:45:36.895656543+00:00"},"epss":{"cve":"CVE-2026-64183","score":0.00119,"percentile":0.01751,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}