{
  "cveId": "CVE-2021-47217",
  "url": "https://patchblox.com/security/cve/CVE-2021-47217",
  "summary": "CVE-2021-47217 is fixed in linux on 1 platform, first by DEBIAN-CVE-2021-47217, released April 10, 2024. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "linux: In the Linux kernel, the following vulnerability has been resolved:  x86/hyperv: Fix NULL deref in set_hv_tscchange_c...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  x86/hyperv: Fix NULL deref in set_hv_tscchange_cb() if Hyper-V setup fails  Check for a valid hv_vp_index array prior to derefencing hv_vp_index when setting Hyper-V\u0027s TSC change callback.  If Hyper-V setup failed in hyperv_init(), the kernel will still report that it\u0027s running under Hyper-V, but will have silently disabled nearly all functionality.    BUG: kernel NULL pointer dereference, address: 0000000000000010   #PF: supervisor read access in kernel mode   #PF: error_code(0x0000) - not-present page   PGD 0 P4D 0   Oops: 0000 [#1] SMP   CPU: 4 PID: 1 Comm: swapper/0 Not tainted 5.15.0-rc2\u002B #75   Hardware name: QEMU Standard PC (Q35 \u002B ICH9, 2009), BIOS 0.0.0 02/06/2015   RIP: 0010:set_hv_tscchange_cb\u002B0x15/0xa0   Code: \u003C8b\u003E 04 82 8b 15 12 17 85 01 48 c1 e0 20 48 0d ee 00 01 00 f6 c6 08   ...   Call Trace:    kvm_arch_init\u002B0x17c/0x280    kvm_init\u002B0x31/0x330    vmx_init\u002B0xba/0x13a    do_one_initcall\u002B0x41/0x1c0    kernel_init_freeable\u002B0x1f2/0x23b    kernel_init\u002B0x16/0x120    ret_from_fork\u002B0x22/0x30",
  "published": "2024-04-10T19:15:48Z",
  "severity": "medium",
  "cvss": 5.5,
  "cvssVector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
  "epss": 0.00235,
  "epssPercentile": 0.14573,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 12.15 (bookworm)",
      "fixedVersion": "5.15.5-1",
      "fix": "DEBIAN-CVE-2021-47217",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2021-47217",
      "released": "2024-04-10T19:15:48Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "5.15.5-1",
      "fix": "DEBIAN-CVE-2021-47217",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2021-47217",
      "released": "2024-04-10T19:15:48Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "5.15.5-1",
      "fix": "DEBIAN-CVE-2021-47217",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2021-47217",
      "released": "2024-04-10T19:15:48Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T19:12:23Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}