{
  "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-2025-39984",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2025-39984",
    "idYear": 2025,
    "status": "PUBLISHED",
    "publishedAt": "2025-10-15T07:56:03.438Z",
    "updatedAt": "2026-05-11T21:40:13.408Z",
    "importedAt": "2026-10-24T01:57:34.152Z",
    "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": "net: tun: Update napi->skb after XDP process",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: tun: Update napi->skb after XDP process\n\nThe syzbot report a UAF issue:\n\n  BUG: KASAN: slab-use-after-free in skb_reset_mac_header include/linux/skbuff.h:3150 [inline]\n  BUG: KASAN: slab-use-after-free in napi_frags_skb net/core/gro.c:723 [inline]\n  BUG: KASAN: slab-use-after-free in napi_gro_frags+0x6e/0x1030 net/core/gro.c:758\n  Read of size 8 at addr ffff88802ef22c18 by task syz.0.17/6079\n  CPU: 0 UID: 0 PID: 6079 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)\n  Call Trace:\n   <TASK>\n   dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120\n   print_address_description mm/kasan/report.c:378 [inline]\n   print_report+0xca/0x240 mm/kasan/report.c:482\n   kasan_report+0x118/0x150 mm/kasan/report.c:595\n   skb_reset_mac_header include/linux/skbuff.h:3150 [inline]\n   napi_frags_skb net/core/gro.c:723 [inline]\n   napi_gro_frags+0x6e/0x1030 net/core/gro.c:758\n   tun_get_user+0x28cb/0x3e20 drivers/net/tun.c:1920\n   tun_chr_write_iter+0x113/0x200 drivers/net/tun.c:1996\n   new_sync_write fs/read_write.c:593 [inline]\n   vfs_write+0x5c9/0xb30 fs/read_write.c:686\n   ksys_write+0x145/0x250 fs/read_write.c:738\n   do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n   do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94\n   entry_SYSCALL_64_after_hwframe+0x77/0x7f\n   </TASK>\n\n  Allocated by task 6079:\n   kasan_save_stack mm/kasan/common.c:47 [inline]\n   kasan_save_track+0x3e/0x80 mm/kasan/common.c:68\n   unpoison_slab_object mm/kasan/common.c:330 [inline]\n   __kasan_mempool_unpoison_object+0xa0/0x170 mm/kasan/common.c:558\n   kasan_mempool_unpoison_object include/linux/kasan.h:388 [inline]\n   napi_skb_cache_get+0x37b/0x6d0 net/core/skbuff.c:295\n   __alloc_skb+0x11e/0x2d0 net/core/skbuff.c:657\n   napi_alloc_skb+0x84/0x7d0 net/core/skbuff.c:811\n   napi_get_frags+0x69/0x140 net/core/gro.c:673\n   tun_napi_alloc_frags drivers/net/tun.c:1404 [inline]\n   tun_get_user+0x77c/0x3e20 drivers/net/tun.c:1784\n   tun_chr_write_iter+0x113/0x200 drivers/net/tun.c:1996\n   new_sync_write fs/read_write.c:593 [inline]\n   vfs_write+0x5c9/0xb30 fs/read_write.c:686\n   ksys_write+0x145/0x250 fs/read_write.c:738\n   do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n   do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94\n   entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\n  Freed by task 6079:\n   kasan_save_stack mm/kasan/common.c:47 [inline]\n   kasan_save_track+0x3e/0x80 mm/kasan/common.c:68\n   kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576\n   poison_slab_object mm/kasan/common.c:243 [inline]\n   __kasan_slab_free+0x5b/0x80 mm/kasan/common.c:275\n   kasan_slab_free include/linux/kasan.h:233 [inline]\n   slab_free_hook mm/slub.c:2422 [inline]\n   slab_free mm/slub.c:4695 [inline]\n   kmem_cache_free+0x18f/0x400 mm/slub.c:4797\n   skb_pp_cow_data+0xdd8/0x13e0 net/core/skbuff.c:969\n   netif_skb_check_for_xdp net/core/dev.c:5390 [inline]\n   netif_receive_generic_xdp net/core/dev.c:5431 [inline]\n   do_xdp_generic+0x699/0x11a0 net/core/dev.c:5499\n   tun_get_user+0x2523/0x3e20 drivers/net/tun.c:1872\n   tun_chr_write_iter+0x113/0x200 drivers/net/tun.c:1996\n   new_sync_write fs/read_write.c:593 [inline]\n   vfs_write+0x5c9/0xb30 fs/read_write.c:686\n   ksys_write+0x145/0x250 fs/read_write.c:738\n   do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n   do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94\n   entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\nAfter commit e6d5dbdd20aa (\"xdp: add multi-buff support for xdp running in\ngeneric mode\"), the original skb may be freed in skb_pp_cow_data() when\nXDP program was attached, which was allocated in tun_napi_alloc_frags().\nHowever, the napi->skb still point to the original skb, update it after\nXDP process.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "e6d5dbdd20aa6a86974af51deb9414cd2e7794cb",
              "status": "affected",
              "versionType": "git",
              "lessThan": "953200d56fc23eebf80a5ad9eed6e2e8a3065093"
            },
            {
              "version": "e6d5dbdd20aa6a86974af51deb9414cd2e7794cb",
              "status": "affected",
              "versionType": "git",
              "lessThan": "1697577e1669b0321d02cd848384a5d33e284296"
            },
            {
              "version": "e6d5dbdd20aa6a86974af51deb9414cd2e7794cb",
              "status": "affected",
              "versionType": "git",
              "lessThan": "1091860a16a86ccdd77c09f2b21a5f634f5ab9ec"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "6.9",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "6.9"
            },
            {
              "version": "6.12.50",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "version": "6.16.10",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.16.*"
            },
            {
              "version": "6.17",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}