{
  "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-2023-53685",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2023-53685",
    "idYear": 2023,
    "status": "PUBLISHED",
    "publishedAt": "2025-10-07T15:21:38.124Z",
    "updatedAt": "2026-05-11T19:49:56.394Z",
    "importedAt": "2026-10-24T01:57:03.413Z",
    "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": "tun: Fix memory leak for detached NAPI queue.",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\ntun: Fix memory leak for detached NAPI queue.\n\nsyzkaller reported [0] memory leaks of sk and skb related to the TUN\ndevice with no repro, but we can reproduce it easily with:\n\n  struct ifreq ifr = {}\n  int fd_tun, fd_tmp;\n  char buf[4] = {};\n\n  fd_tun = openat(AT_FDCWD, \"/dev/net/tun\", O_WRONLY, 0);\n  ifr.ifr_flags = IFF_TUN | IFF_NAPI | IFF_MULTI_QUEUE;\n  ioctl(fd_tun, TUNSETIFF, &ifr);\n\n  ifr.ifr_flags = IFF_DETACH_QUEUE;\n  ioctl(fd_tun, TUNSETQUEUE, &ifr);\n\n  fd_tmp = socket(AF_PACKET, SOCK_PACKET, 0);\n  ifr.ifr_flags = IFF_UP;\n  ioctl(fd_tmp, SIOCSIFFLAGS, &ifr);\n\n  write(fd_tun, buf, sizeof(buf));\n  close(fd_tun);\n\nIf we enable NAPI and multi-queue on a TUN device, we can put skb into\ntfile->sk.sk_write_queue after the queue is detached.  We should prevent\nit by checking tfile->detached before queuing skb.\n\nNote this must be done under tfile->sk.sk_write_queue.lock because write()\nand ioctl(IFF_DETACH_QUEUE) can run concurrently.  Otherwise, there would\nbe a small race window:\n\n  write()                             ioctl(IFF_DETACH_QUEUE)\n  `- tun_get_user                     `- __tun_detach\n     |- if (tfile->detached)             |- tun_disable_queue\n     |  `-> false                        |  `- tfile->detached = tun\n     |                                   `- tun_queue_purge\n     |- spin_lock_bh(&queue->lock)\n     `- __skb_queue_tail(queue, skb)\n\nAnother solution is to call tun_queue_purge() when closing and\nreattaching the detached queue, but it could paper over another\nproblems.  Also, we do the same kind of test for IFF_NAPI_FRAGS.\n\n[0]:\nunreferenced object 0xffff88801edbc800 (size 2048):\n  comm \"syz-executor.1\", pid 33269, jiffies 4295743834 (age 18.756s)\n  hex dump (first 32 bytes):\n    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................\n    00 00 07 40 00 00 00 00 00 00 00 00 00 00 00 00  ...@............\n  backtrace:\n    [<000000008c16ea3d>] __do_kmalloc_node mm/slab_common.c:965 [inline]\n    [<000000008c16ea3d>] __kmalloc+0x4a/0x130 mm/slab_common.c:979\n    [<000000003addde56>] kmalloc include/linux/slab.h:563 [inline]\n    [<000000003addde56>] sk_prot_alloc+0xef/0x1b0 net/core/sock.c:2035\n    [<000000003e20621f>] sk_alloc+0x36/0x2f0 net/core/sock.c:2088\n    [<0000000028e43843>] tun_chr_open+0x3d/0x190 drivers/net/tun.c:3438\n    [<000000001b0f1f28>] misc_open+0x1a6/0x1f0 drivers/char/misc.c:165\n    [<000000004376f706>] chrdev_open+0x111/0x300 fs/char_dev.c:414\n    [<00000000614d379f>] do_dentry_open+0x2f9/0x750 fs/open.c:920\n    [<000000008eb24774>] do_open fs/namei.c:3636 [inline]\n    [<000000008eb24774>] path_openat+0x143f/0x1a30 fs/namei.c:3791\n    [<00000000955077b5>] do_filp_open+0xce/0x1c0 fs/namei.c:3818\n    [<00000000b78973b0>] do_sys_openat2+0xf0/0x260 fs/open.c:1356\n    [<00000000057be699>] do_sys_open fs/open.c:1372 [inline]\n    [<00000000057be699>] __do_sys_openat fs/open.c:1388 [inline]\n    [<00000000057be699>] __se_sys_openat fs/open.c:1383 [inline]\n    [<00000000057be699>] __x64_sys_openat+0x83/0xf0 fs/open.c:1383\n    [<00000000a7d2182d>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n    [<00000000a7d2182d>] do_syscall_64+0x3c/0x90 arch/x86/entry/common.c:80\n    [<000000004cc4e8c4>] entry_SYSCALL_64_after_hwframe+0x72/0xdc\n\nunreferenced object 0xffff88802f671700 (size 240):\n  comm \"syz-executor.1\", pid 33269, jiffies 4295743854 (age 18.736s)\n  hex dump (first 32 bytes):\n    68 c9 db 1e 80 88 ff ff 68 c9 db 1e 80 88 ff ff  h.......h.......\n    00 c0 7b 2f 80 88 ff ff 00 c8 db 1e 80 88 ff ff  ..{/............\n  backtrace:\n    [<00000000e9d9fdb6>] __alloc_skb+0x223/0x250 net/core/skbuff.c:644\n    [<000000002c3e4e0b>] alloc_skb include/linux/skbuff.h:1288 [inline]\n    [<000000002c3e4e0b>] alloc_skb_with_frags+0x6f/0x350 net/core/skbuff.c:6378\n    [<00000000825f98d7>] sock_alloc_send_pskb+0x3ac/0x3e0 net/core/sock.c:2729\n    [<00000000e9eb3df3>] tun_alloc_skb drivers/net/tun.c:1529 [inline]\n    [<\n---truncated---",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "cde8b15f1aabe327038ee4e0e11dd6b798572f69",
              "status": "affected",
              "versionType": "git",
              "lessThan": "9cae243b9ae25adfe468cd47ceca591f6725b79c"
            },
            {
              "version": "cde8b15f1aabe327038ee4e0e11dd6b798572f69",
              "status": "affected",
              "versionType": "git",
              "lessThan": "0d20210a190f76db9ec35ee4e0fc77e6c7a148f5"
            },
            {
              "version": "cde8b15f1aabe327038ee4e0e11dd6b798572f69",
              "status": "affected",
              "versionType": "git",
              "lessThan": "82b2bc279467c875ec36f8ef820f00997c2a4e8e"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "3.8",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "3.8"
            },
            {
              "version": "6.1.30",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "version": "6.3.4",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.3.*"
            },
            {
              "version": "6.4",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}