{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2021-47299",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2021-47299",
    "idYear": 2021,
    "status": "PUBLISHED",
    "publishedAt": "2024-05-21T14:35:21.276Z",
    "updatedAt": "2026-05-11T13:51:48.198Z",
    "importedAt": "2026-10-24T01:56:36.661Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "xdp, net: Fix use-after-free in bpf_xdp_link_release",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nxdp, net: Fix use-after-free in bpf_xdp_link_release\n\nThe problem occurs between dev_get_by_index() and dev_xdp_attach_link().\nAt this point, dev_xdp_uninstall() is called. Then xdp link will not be\ndetached automatically when dev is released. But link->dev already\npoints to dev, when xdp link is released, dev will still be accessed,\nbut dev has been released.\n\ndev_get_by_index()        |\nlink->dev = dev           |\n                          |      rtnl_lock()\n                          |      unregister_netdevice_many()\n                          |          dev_xdp_uninstall()\n                          |      rtnl_unlock()\nrtnl_lock();              |\ndev_xdp_attach_link()     |\nrtnl_unlock();            |\n                          |      netdev_run_todo() // dev released\nbpf_xdp_link_release()    |\n    /* access dev.        |\n       use-after-free */  |\n\n[   45.966867] BUG: KASAN: use-after-free in bpf_xdp_link_release+0x3b8/0x3d0\n[   45.967619] Read of size 8 at addr ffff00000f9980c8 by task a.out/732\n[   45.968297]\n[   45.968502] CPU: 1 PID: 732 Comm: a.out Not tainted 5.13.0+ #22\n[   45.969222] Hardware name: linux,dummy-virt (DT)\n[   45.969795] Call trace:\n[   45.970106]  dump_backtrace+0x0/0x4c8\n[   45.970564]  show_stack+0x30/0x40\n[   45.970981]  dump_stack_lvl+0x120/0x18c\n[   45.971470]  print_address_description.constprop.0+0x74/0x30c\n[   45.972182]  kasan_report+0x1e8/0x200\n[   45.972659]  __asan_report_load8_noabort+0x2c/0x50\n[   45.973273]  bpf_xdp_link_release+0x3b8/0x3d0\n[   45.973834]  bpf_link_free+0xd0/0x188\n[   45.974315]  bpf_link_put+0x1d0/0x218\n[   45.974790]  bpf_link_release+0x3c/0x58\n[   45.975291]  __fput+0x20c/0x7e8\n[   45.975706]  ____fput+0x24/0x30\n[   45.976117]  task_work_run+0x104/0x258\n[   45.976609]  do_notify_resume+0x894/0xaf8\n[   45.977121]  work_pending+0xc/0x328\n[   45.977575]\n[   45.977775] The buggy address belongs to the page:\n[   45.978369] page:fffffc00003e6600 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4f998\n[   45.979522] flags: 0x7fffe0000000000(node=0|zone=0|lastcpupid=0x3ffff)\n[   45.980349] raw: 07fffe0000000000 fffffc00003e6708 ffff0000dac3c010 0000000000000000\n[   45.981309] raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000\n[   45.982259] page dumped because: kasan: bad access detected\n[   45.982948]\n[   45.983153] Memory state around the buggy address:\n[   45.983753]  ffff00000f997f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc\n[   45.984645]  ffff00000f998000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff\n[   45.985533] >ffff00000f998080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff\n[   45.986419]                                               ^\n[   45.987112]  ffff00000f998100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff\n[   45.988006]  ffff00000f998180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff\n[   45.988895] ==================================================================\n[   45.989773] Disabling lock debugging due to kernel taint\n[   45.990552] Kernel panic - not syncing: panic_on_warn set ...\n[   45.991166] CPU: 1 PID: 732 Comm: a.out Tainted: G    B             5.13.0+ #22\n[   45.991929] Hardware name: linux,dummy-virt (DT)\n[   45.992448] Call trace:\n[   45.992753]  dump_backtrace+0x0/0x4c8\n[   45.993208]  show_stack+0x30/0x40\n[   45.993627]  dump_stack_lvl+0x120/0x18c\n[   45.994113]  dump_stack+0x1c/0x34\n[   45.994530]  panic+0x3a4/0x7d8\n[   45.994930]  end_report+0x194/0x198\n[   45.995380]  kasan_report+0x134/0x200\n[   45.995850]  __asan_report_load8_noabort+0x2c/0x50\n[   45.996453]  bpf_xdp_link_release+0x3b8/0x3d0\n[   45.997007]  bpf_link_free+0xd0/0x188\n[   45.997474]  bpf_link_put+0x1d0/0x218\n[   45.997942]  bpf_link_release+0x3c/0x58\n[   45.998429]  __fput+0x20c/0x7e8\n[   45.998833]  ____fput+0x24/0x30\n[   45.999247]  task_work_run+0x104/0x258\n[   45.999731]  do_notify_resume+0x894/0xaf8\n[   46.000236]  work_pending\n---truncated---",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "aa8d3a716b59db6c1ad6c68fb8aa05e31980da60",
              "status": "affected",
              "versionType": "git",
              "lessThan": "ca9ba1de8f09976b45ccc8e655c51c6201992139"
            },
            {
              "version": "aa8d3a716b59db6c1ad6c68fb8aa05e31980da60",
              "status": "affected",
              "versionType": "git",
              "lessThan": "a7537dc73e69ad9c0b67ad24ad3ebee954ed0af6"
            },
            {
              "version": "aa8d3a716b59db6c1ad6c68fb8aa05e31980da60",
              "status": "affected",
              "versionType": "git",
              "lessThan": "5acc7d3e8d342858405fbbc671221f676b547ce7"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "5.9",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "5.9"
            },
            {
              "version": "5.10.54",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "version": "5.13.6",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.13.*"
            },
            {
              "version": "5.14",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}