{
  "cveId": "CVE-2021-47237",
  "url": "https://patchblox.com/security/cve/CVE-2021-47237",
  "summary": "CVE-2021-47237 is fixed in linux on 1 platform, first by DEBIAN-CVE-2021-47237, released May 21, 2024. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "linux: In the Linux kernel, the following vulnerability has been resolved:  net: hamradio: fix memory leak in mkiss_close  M...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  net: hamradio: fix memory leak in mkiss_close  My local syzbot instance hit memory leak in mkiss_open()[1]. The problem was in missing free_netdev() in mkiss_close().  In mkiss_open() netdevice is allocated and then registered, but in mkiss_close() netdevice was only unregistered, but not freed.  Fail log:  BUG: memory leak unreferenced object 0xffff8880281ba000 (size 4096):   comm \u0022syz-executor.1\u0022, pid 11443, jiffies 4295046091 (age 17.660s)   hex dump (first 32 bytes):     61 78 30 00 00 00 00 00 00 00 00 00 00 00 00 00  ax0.............     00 27 fa 2a 80 88 ff ff 00 00 00 00 00 00 00 00  .\u0027.*............   backtrace:     [\u003Cffffffff81a27201\u003E] kvmalloc_node\u002B0x61/0xf0     [\u003Cffffffff8706e7e8\u003E] alloc_netdev_mqs\u002B0x98/0xe80     [\u003Cffffffff84e64192\u003E] mkiss_open\u002B0xb2/0x6f0 [1]     [\u003Cffffffff842355db\u003E] tty_ldisc_open\u002B0x9b/0x110     [\u003Cffffffff84236488\u003E] tty_set_ldisc\u002B0x2e8/0x670     [\u003Cffffffff8421f7f3\u003E] tty_ioctl\u002B0xda3/0x1440     [\u003Cffffffff81c9f273\u003E] __x64_sys_ioctl\u002B0x193/0x200     [\u003Cffffffff8911263a\u003E] do_syscall_64\u002B0x3a/0xb0     [\u003Cffffffff89200068\u003E] entry_SYSCALL_64_after_hwframe\u002B0x44/0xae  BUG: memory leak unreferenced object 0xffff8880141a9a00 (size 96):   comm \u0022syz-executor.1\u0022, pid 11443, jiffies 4295046091 (age 17.660s)   hex dump (first 32 bytes):     e8 a2 1b 28 80 88 ff ff e8 a2 1b 28 80 88 ff ff  ...(.......(....     98 92 9c aa b0 40 02 00 00 00 00 00 00 00 00 00  .....@..........   backtrace:     [\u003Cffffffff8709f68b\u003E] __hw_addr_create_ex\u002B0x5b/0x310     [\u003Cffffffff8709fb38\u003E] __hw_addr_add_ex\u002B0x1f8/0x2b0     [\u003Cffffffff870a0c7b\u003E] dev_addr_init\u002B0x10b/0x1f0     [\u003Cffffffff8706e88b\u003E] alloc_netdev_mqs\u002B0x13b/0xe80     [\u003Cffffffff84e64192\u003E] mkiss_open\u002B0xb2/0x6f0 [1]     [\u003Cffffffff842355db\u003E] tty_ldisc_open\u002B0x9b/0x110     [\u003Cffffffff84236488\u003E] tty_set_ldisc\u002B0x2e8/0x670     [\u003Cffffffff8421f7f3\u003E] tty_ioctl\u002B0xda3/0x1440     [\u003Cffffffff81c9f273\u003E] __x64_sys_ioctl\u002B0x193/0x200     [\u003Cffffffff8911263a\u003E] do_syscall_64\u002B0x3a/0xb0     [\u003Cffffffff89200068\u003E] entry_SYSCALL_64_after_hwframe\u002B0x44/0xae  BUG: memory leak unreferenced object 0xffff8880219bfc00 (size 512):   comm \u0022syz-executor.1\u0022, pid 11443, jiffies 4295046091 (age 17.660s)   hex dump (first 32 bytes):     00 a0 1b 28 80 88 ff ff 80 8f b1 8d ff ff ff ff  ...(............     80 8f b1 8d ff ff ff ff 00 00 00 00 00 00 00 00  ................   backtrace:     [\u003Cffffffff81a27201\u003E] kvmalloc_node\u002B0x61/0xf0     [\u003Cffffffff8706eec7\u003E] alloc_netdev_mqs\u002B0x777/0xe80     [\u003Cffffffff84e64192\u003E] mkiss_open\u002B0xb2/0x6f0 [1]     [\u003Cffffffff842355db\u003E] tty_ldisc_open\u002B0x9b/0x110     [\u003Cffffffff84236488\u003E] tty_set_ldisc\u002B0x2e8/0x670     [\u003Cffffffff8421f7f3\u003E] tty_ioctl\u002B0xda3/0x1440     [\u003Cffffffff81c9f273\u003E] __x64_sys_ioctl\u002B0x193/0x200     [\u003Cffffffff8911263a\u003E] do_syscall_64\u002B0x3a/0xb0     [\u003Cffffffff89200068\u003E] entry_SYSCALL_64_after_hwframe\u002B0x44/0xae  BUG: memory leak unreferenced object 0xffff888029b2b200 (size 256):   comm \u0022syz-executor.1\u0022, pid 11443, jiffies 4295046091 (age 17.660s)   hex dump (first 32 bytes):     00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................     00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................   backtrace:     [\u003Cffffffff81a27201\u003E] kvmalloc_node\u002B0x61/0xf0     [\u003Cffffffff8706f062\u003E] alloc_netdev_mqs\u002B0x912/0xe80     [\u003Cffffffff84e64192\u003E] mkiss_open\u002B0xb2/0x6f0 [1]     [\u003Cffffffff842355db\u003E] tty_ldisc_open\u002B0x9b/0x110     [\u003Cffffffff84236488\u003E] tty_set_ldisc\u002B0x2e8/0x670     [\u003Cffffffff8421f7f3\u003E] tty_ioctl\u002B0xda3/0x1440     [\u003Cffffffff81c9f273\u003E] __x64_sys_ioctl\u002B0x193/0x200     [\u003Cffffffff8911263a\u003E] do_syscall_64\u002B0x3a/0xb0     [\u003Cffffffff89200068\u003E] entry_SYSCALL_64_after_hwframe\u002B0x44/0xae",
  "published": "2024-05-21T15:15:12Z",
  "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": 0.00226,
  "epssPercentile": 0.13387,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 12.15 (bookworm)",
      "fixedVersion": "5.10.46-1",
      "fix": "DEBIAN-CVE-2021-47237",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2021-47237",
      "released": "2024-05-21T15:15:12Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "5.10.46-1",
      "fix": "DEBIAN-CVE-2021-47237",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2021-47237",
      "released": "2024-05-21T15:15:12Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "5.10.46-1",
      "fix": "DEBIAN-CVE-2021-47237",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2021-47237",
      "released": "2024-05-21T15:15:12Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T06:59:42Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}