{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "7.0.12-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "In the Linux kernel, the following vulnerability has been resolved:  x86/mm: Disable broadcast TLB flush when PCID is disabled  Booting with \"nopcid\" clears X86_FEATURE_PCID and keeps CR4.PCIDE from being set to one. On AMD CPUs that support INVLPGB, broadcast TLB flushing remains enabled.  There are two checks that decide whether the global ASID code runs, mm_global_asid() and consider_global_asid(), that key off of the X86_FEATURE_INVLPGB feature. Once an mm becomes active on more than three CPUs, consider_global_asid() assigns it a global ASID, after which flush_tlb_mm_range() takes the broadcast_tlb_flush() path using a non-zero PCID. Issuing an INVLPGB with a non-zero PCID while CR4.PCIDE is not set results in a #GP:    Oops: general protection fault, kernel NULL pointer dereference 0x1: 0000 [#1] SMP NOPTI   CPU: 158 UID: 0 PID: 3119 Comm: snap Not tainted 7.1.0-rc3 #1 PREEMPT(full)   Hardware name: ...   RIP: 0010:broadcast_tlb_flush   Code: ... 89 da 48 83 c8 07 \u003c0f\u003e 01 fe eb 08 cc cc cc ...   Call Trace:    \u003cTASK\u003e    flush_tlb_mm_range    ptep_clear_flush    wp_page_copy    ? _raw_spin_unlock    __handle_mm_fault    handle_mm_fault    do_user_addr_fault    exc_page_fault    asm_exc_page_fault  All processors that support broadcast TLB invalidation also have PCID support, so it is only the \"nopcid\" scenario that is of concern. In this situation just disable the broadcast TLB support using the CPUID dependency support by making X86_FEATURE_INVLPGB dependent on X86_FEATURE_PCID.    [ bp: Massage commit message. ]",
  "id": "DEBIAN-CVE-2026-64229",
  "modified": "2026-09-14T16:47:47.794796887Z",
  "published": "2026-07-24T16:16:52.023Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-64229"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "upstream": [
    "CVE-2026-64229"
  ]
}