{"cve":"CVE-2026-46290","nvd":{"published":"2026-06-08T17:16:47.230","modified":"2026-07-23T08:10:00.137","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nx86/efi: Fix graceful fault handling after FPU softirq changes\n\nSince commit d02198550423 (\"x86/fpu: Improve crypto performance by\nmaking kernel-mode FPU reliably usable in softirqs\"), kernel_fpu_begin()\ncalls fpregs_lock() which uses local_bh_disable() instead of the\nprevious preempt_disable(). This sets SOFTIRQ_OFFSET in preempt_count\nduring the entire EFI runtime service call, causing in_interrupt() to\nreturn true in normal task context.\n\nThe graceful page fault handler efi_crash_gracefully_on_page_fault()\nuses in_interrupt() to bail out for faults in real interrupt context.\nWith SOFTIRQ_OFFSET now set, the handler always bails out, leaving EFI\nfirmware page faults unhandled. This escalates to die() which also sees\nin_interrupt() as true and calls panic(\"Fatal exception in interrupt\"),\nresulting in a hard system freeze. On systems with buggy firmware that\ntriggers page faults during EFI runtime calls (e.g., accessing unmapped\nmemory in GetTime()), this causes an unrecoverable hang instead of the\nexpected graceful EFI_ABORTED recovery.\n\nFix by replacing in_interrupt() with !in_task(). This preserves the\noriginal intent of bailing for interrupts or NMI faults, while no longer\nfalsely triggering from the FPU code path's local_bh_disable().\n\n[ardb: Sashiko spotted that using 'in_hardirq() || in_nmi()' leaves a\n       window where a softirq may be taken before fpregs_lock() is\n       called, but after efi_rts_work.efi_rts_id has been assigned,\n       and any page faults occurring in that window will then be\n       misidentified as having been caused by the firmware. Instead,\n       use !in_task(), which incorporates in_serving_softirq(). ]","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":[],"references":["https://git.kernel.org/stable/c/088f65e206087bf903743bd18417261d7a4c9644","https://git.kernel.org/stable/c/22b365ba1af3d8c6036b8e5112fffe80998b85a0","https://git.kernel.org/stable/c/db155b86d1523e85941f61efd7d7ffb594cc9a29"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:38:48.522727527+00:00"},"epss":{"cve":"CVE-2026-46290","score":0.00121,"percentile":0.0187,"date":"2026-10-31"},"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."]}