Vulnerability-Lookup

FKIE_CVE-2024-56635

Vulnerability from fkie_nvd - Published: 2024-12-27 15:15 - Updated: 2026-06-17 08:12

Severity

7.0 (High) - CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Summary

In the Linux kernel, the following vulnerability has been resolved: net: avoid potential UAF in default_operstate() syzbot reported an UAF in default_operstate() [1] Issue is a race between device and netns dismantles. After calling __rtnl_unlock() from netdev_run_todo(), we can not assume the netns of each device is still alive. Make sure the device is not in NETREG_UNREGISTERED state, and add an ASSERT_RTNL() before the call to __dev_get_by_index(). We might move this ASSERT_RTNL() in __dev_get_by_index() in the future. [1] BUG: KASAN: slab-use-after-free in __dev_get_by_index+0x5d/0x110 net/core/dev.c:852 Read of size 8 at addr ffff888043eba1b0 by task syz.0.0/5339 CPU: 0 UID: 0 PID: 5339 Comm: syz.0.0 Not tainted 6.12.0-syzkaller-10296-gaaf20f870da0 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x169/0x550 mm/kasan/report.c:489 kasan_report+0x143/0x180 mm/kasan/report.c:602 __dev_get_by_index+0x5d/0x110 net/core/dev.c:852 default_operstate net/core/link_watch.c:51 [inline] rfc2863_policy+0x224/0x300 net/core/link_watch.c:67 linkwatch_do_dev+0x3e/0x170 net/core/link_watch.c:170 netdev_run_todo+0x461/0x1000 net/core/dev.c:10894 rtnl_unlock net/core/rtnetlink.c:152 [inline] rtnl_net_unlock include/linux/rtnetlink.h:133 [inline] rtnl_dellink+0x760/0x8d0 net/core/rtnetlink.c:3520 rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6911 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2541 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline] netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1347 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1891 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:726 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2583 ___sys_sendmsg net/socket.c:2637 [inline] __sys_sendmsg+0x269/0x350 net/socket.c:2669 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2a3cb80809 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2a3d9cd058 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f2a3cd45fa0 RCX: 00007f2a3cb80809 RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000008 RBP: 00007f2a3cbf393e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f2a3cd45fa0 R15: 00007ffd03bc65c8 </TASK> Allocated by task 5339: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4314 kmalloc_noprof include/linux/slab.h:901 [inline] kmalloc_array_noprof include/linux/slab.h:945 [inline] netdev_create_hash net/core/dev.c:11870 [inline] netdev_init+0x10c/0x250 net/core/dev.c:11890 ops_init+0x31e/0x590 net/core/net_namespace.c:138 setup_net+0x287/0x9e0 net/core/net_namespace.c:362 copy_net_ns+0x33f/0x570 net/core/net_namespace.c:500 create_new_namespaces+0x425/0x7b0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228 ksys_unshare+0x57d/0xa70 kernel/fork.c:3314 __do_sys_unshare kernel/fork.c:3385 [inline] __se_sys_unshare kernel/fork.c:3383 [inline] __x64_sys_unshare+0x38/0x40 kernel/fork.c:3383 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x8 ---truncated---

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/316183d58319f191e16503bc2dffa156c4442df2	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/3265aab0736f78bb218200b06b1abb525c316269	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/750e51603395e755537da08f745864c93e3ce741	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	6.13

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/core/link_watch.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "3265aab0736f78bb218200b06b1abb525c316269",
              "status": "affected",
              "version": "8c55facecd7ade835287298ce325f930d888d8ec",
              "versionType": "git"
            },
            {
              "lessThan": "316183d58319f191e16503bc2dffa156c4442df2",
              "status": "affected",
              "version": "8c55facecd7ade835287298ce325f930d888d8ec",
              "versionType": "git"
            },
            {
              "lessThan": "750e51603395e755537da08f745864c93e3ce741",
              "status": "affected",
              "version": "8c55facecd7ade835287298ce325f930d888d8ec",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/core/link_watch.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.2"
            },
            {
              "lessThan": "6.2",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.66",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.13",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "29A976AD-B9AB-4A95-9F08-7669F8847EB9",
              "versionEndExcluding": "6.6.66",
              "versionStartIncluding": "6.2",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "9501D045-7A94-42CA-8B03-821BE94A65B7",
              "versionEndExcluding": "6.12.5",
              "versionStartIncluding": "6.7",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc1:*:*:*:*:*:*",
              "matchCriteriaId": "62567B3C-6CEE-46D0-BC2E-B3717FBF7D13",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: avoid potential UAF in default_operstate()\n\nsyzbot reported an UAF in default_operstate() [1]\n\nIssue is a race between device and netns dismantles.\n\nAfter calling __rtnl_unlock() from netdev_run_todo(),\nwe can not assume the netns of each device is still alive.\n\nMake sure the device is not in NETREG_UNREGISTERED state,\nand add an ASSERT_RTNL() before the call to\n__dev_get_by_index().\n\nWe might move this ASSERT_RTNL() in __dev_get_by_index()\nin the future.\n\n[1]\n\nBUG: KASAN: slab-use-after-free in __dev_get_by_index+0x5d/0x110 net/core/dev.c:852\nRead of size 8 at addr ffff888043eba1b0 by task syz.0.0/5339\n\nCPU: 0 UID: 0 PID: 5339 Comm: syz.0.0 Not tainted 6.12.0-syzkaller-10296-gaaf20f870da0 #0\nHardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014\nCall Trace:\n \u003cTASK\u003e\n  __dump_stack lib/dump_stack.c:94 [inline]\n  dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120\n  print_address_description mm/kasan/report.c:378 [inline]\n  print_report+0x169/0x550 mm/kasan/report.c:489\n  kasan_report+0x143/0x180 mm/kasan/report.c:602\n  __dev_get_by_index+0x5d/0x110 net/core/dev.c:852\n  default_operstate net/core/link_watch.c:51 [inline]\n  rfc2863_policy+0x224/0x300 net/core/link_watch.c:67\n  linkwatch_do_dev+0x3e/0x170 net/core/link_watch.c:170\n  netdev_run_todo+0x461/0x1000 net/core/dev.c:10894\n  rtnl_unlock net/core/rtnetlink.c:152 [inline]\n  rtnl_net_unlock include/linux/rtnetlink.h:133 [inline]\n  rtnl_dellink+0x760/0x8d0 net/core/rtnetlink.c:3520\n  rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6911\n  netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2541\n  netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline]\n  netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1347\n  netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1891\n  sock_sendmsg_nosec net/socket.c:711 [inline]\n  __sock_sendmsg+0x221/0x270 net/socket.c:726\n  ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2583\n  ___sys_sendmsg net/socket.c:2637 [inline]\n  __sys_sendmsg+0x269/0x350 net/socket.c:2669\n  do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n  do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\nRIP: 0033:0x7f2a3cb80809\nCode: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 \u003c48\u003e 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48\nRSP: 002b:00007f2a3d9cd058 EFLAGS: 00000246 ORIG_RAX: 000000000000002e\nRAX: ffffffffffffffda RBX: 00007f2a3cd45fa0 RCX: 00007f2a3cb80809\nRDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000008\nRBP: 00007f2a3cbf393e R08: 0000000000000000 R09: 0000000000000000\nR10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000\nR13: 0000000000000000 R14: 00007f2a3cd45fa0 R15: 00007ffd03bc65c8\n \u003c/TASK\u003e\n\nAllocated by task 5339:\n  kasan_save_stack mm/kasan/common.c:47 [inline]\n  kasan_save_track+0x3f/0x80 mm/kasan/common.c:68\n  poison_kmalloc_redzone mm/kasan/common.c:377 [inline]\n  __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394\n  kasan_kmalloc include/linux/kasan.h:260 [inline]\n  __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4314\n  kmalloc_noprof include/linux/slab.h:901 [inline]\n  kmalloc_array_noprof include/linux/slab.h:945 [inline]\n  netdev_create_hash net/core/dev.c:11870 [inline]\n  netdev_init+0x10c/0x250 net/core/dev.c:11890\n  ops_init+0x31e/0x590 net/core/net_namespace.c:138\n  setup_net+0x287/0x9e0 net/core/net_namespace.c:362\n  copy_net_ns+0x33f/0x570 net/core/net_namespace.c:500\n  create_new_namespaces+0x425/0x7b0 kernel/nsproxy.c:110\n  unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228\n  ksys_unshare+0x57d/0xa70 kernel/fork.c:3314\n  __do_sys_unshare kernel/fork.c:3385 [inline]\n  __se_sys_unshare kernel/fork.c:3383 [inline]\n  __x64_sys_unshare+0x38/0x40 kernel/fork.c:3383\n  do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n  do_syscall_64+0xf3/0x230 arch/x8\n---truncated---"
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: net: evitar un UAF potencial en default_operstate() syzbot inform\u00f3 un UAF en default_operstate() [1] El problema es una carrera entre el desmantelamiento de dispositivos y redes. Despu\u00e9s de llamar a __rtnl_unlock() desde netdev_run_todo(), no podemos asumir que las redes de cada dispositivo a\u00fan est\u00e9n activas. Aseg\u00farese de que el dispositivo no est\u00e9 en estado NETREG_UNREGISTERED y agregue un ASSERT_RTNL() antes de la llamada a __dev_get_by_index(). Es posible que movamos este ASSERT_RTNL() a __dev_get_by_index() en el futuro. [1] ERROR: KASAN: slab-use-after-free en __dev_get_by_index+0x5d/0x110 net/core/dev.c:852 Lectura de tama\u00f1o 8 en la direcci\u00f3n ffff888043eba1b0 por la tarea syz.0.0/5339 CPU: 0 UID: 0 PID: 5339 Comm: syz.0.0 No contaminado 6.12.0-syzkaller-10296-gaaf20f870da0 #0 Nombre del hardware: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Seguimiento de llamadas:  __dump_stack lib/dump_stack.c:94 [en l\u00ednea] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 imprimir_direcci\u00f3n_descripci\u00f3n mm/kasan/report.c:378 [en l\u00ednea] imprimir_report+0x169/0x550 mm/kasan/report.c:489 kasan_report+0x143/0x180 mm/kasan/report.c:602 __dev_get_by_index+0x5d/0x110 net/core/dev.c:852 estado_operaci\u00f3n_predeterminado net/core/link_watch.c:51 [en l\u00ednea] rfc2863_policy+0x224/0x300 net/core/link_watch.c:67 linkwatch_do_dev+0x3e/0x170 net/core/link_watch.c:170 netdev_run_todo+0x461/0x1000 net/core/dev.c:10894 rtnl_unlock net/core/rtnetlink.c:152 [en l\u00ednea] rtnl_net_unlock include/linux/rtnetlink.h:133 [en l\u00ednea] rtnl_dellink+0x760/0x8d0 net/core/rtnetlink.c:3520 rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6911 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2541 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [en l\u00ednea] netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1347 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1891 sock_sendmsg_nosec net/socket.c:711 [en l\u00ednea] __sock_sendmsg+0x221/0x270 net/socket.c:726 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2583 ___sys_sendmsg net/socket.c:2637 [en l\u00ednea] __sys_sendmsg+0x269/0x350 net/socket.c:2669 do_syscall_x64 arch/x86/entry/common.c:52 [en l\u00ednea] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2a3cb80809 C\u00f3digo: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 \u0026lt;48\u0026gt; 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2a3d9cd058 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f2a3cd45fa0 RCX: 00007f2a3cb80809 RDX: 000000000000000 RSI: 0000000020000000 RDI: 0000000000000008 RBP: 00007f2a3cbf393e R08: 000000000000000 R09: 0000000000000000 R10: 00000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f2a3cd45fa0 R15: 00007ffd03bc65c8  Asignado por la tarea 5339: kasan_save_stack mm/kasan/common.c:47 [en l\u00ednea] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [en l\u00ednea] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc incluir/linux/kasan.h:260 [en l\u00ednea] __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4314 kmalloc_noprof incluir/linux/slab.h:901 [en l\u00ednea] kmalloc_array_noprof incluir/linux/slab.h:945 [en l\u00ednea] netdev_create_hash net/core/dev.c:11870 [en l\u00ednea] netdev_init+0x10c/0x250 net/core/dev.c:11890 ops_init+0x31e/0x590 net/core/net_namespace.c:138 setup_net+0x287/0x9e0 net/core/net_namespace.c:362 copy_net_ns+0x33f/0x570 net/core/net_namespace.c:500 crear_nuevos_espacios_de_nombres+0x425/0x7b0 kernel/nsproxy.c:110 dejar_de_compartir_espacios_de_nombres_nsproxy+0x124/0x180 kernel/nsproxy.c:228 dejar_de_compartir_ksys+0x57d/0xa70 kernel/fork.c:3314 __do_sys_unshare kernel/fork.c:3385 [en l\u00ednea] __se_sys_unshare kernel/fork.c:3383 [en l\u00ednea] __x64_sys_unshare+0x38/0x40 ---truncado---"
    }
  ],
  "id": "CVE-2024-56635",
  "lastModified": "2026-06-17T08:12:36.460",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 7.0,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.0,
        "impactScore": 5.9,
        "source": "nvd@nist.gov",
        "type": "Primary"
      },
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2024-56635",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2025-02-10T17:12:40.278798Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2024-12-27T15:15:23.207",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/316183d58319f191e16503bc2dffa156c4442df2"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/3265aab0736f78bb218200b06b1abb525c316269"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/750e51603395e755537da08f745864c93e3ce741"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-362"
        },
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}

CVE-2024-56635 (GCVE-0-2024-56635)

Vulnerability from cvelistv5 – Published: 2024-12-27 15:02 – Updated: 2026-08-05 11:45

Title

net: avoid potential UAF in default_operstate()

Summary

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2025-02-10 17:12 UTC

CWE

CWE-416 - Use After Free

Assigner

Linux mitre root

References

3 references

URL	Tags
https://git.kernel.org/stable/c/3265aab0736f78bb2…
https://git.kernel.org/stable/c/316183d58319f191e…
https://git.kernel.org/stable/c/750e51603395e7555…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 8c55facecd7ade835287298ce325f930d888d8ec , < 3265aab0736f78bb218200b06b1abb525c316269 (git) Affected: 8c55facecd7ade835287298ce325f930d888d8ec , < 316183d58319f191e16503bc2dffa156c4442df2 (git) Affected: 8c55facecd7ade835287298ce325f930d888d8ec , < 750e51603395e755537da08f745864c93e3ce741 (git)
Linux	Linux	Affected: 6.2 Unaffected: 0 , < 6.2 (semver) Unaffected: 6.6.66 , ≤ 6.6.* (semver) Unaffected: 6.12.5 , ≤ 6.12.* (semver) Unaffected: 6.13 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "LOCAL",
              "availabilityImpact": "HIGH",
              "baseScore": 7.8,
              "baseSeverity": "HIGH",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "HIGH",
              "privilegesRequired": "LOW",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2024-56635",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-02-10T17:12:40.278798Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-416",
                "description": "CWE-416 Use After Free",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-02-10T17:21:08.285Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/core/link_watch.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "3265aab0736f78bb218200b06b1abb525c316269",
              "status": "affected",
              "version": "8c55facecd7ade835287298ce325f930d888d8ec",
              "versionType": "git"
            },
            {
              "lessThan": "316183d58319f191e16503bc2dffa156c4442df2",
              "status": "affected",
              "version": "8c55facecd7ade835287298ce325f930d888d8ec",
              "versionType": "git"
            },
            {
              "lessThan": "750e51603395e755537da08f745864c93e3ce741",
              "status": "affected",
              "version": "8c55facecd7ade835287298ce325f930d888d8ec",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/core/link_watch.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.2"
            },
            {
              "lessThan": "6.2",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.66",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.13",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.66",
                  "versionStartIncluding": "6.2",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.5",
                  "versionStartIncluding": "6.2",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.13",
                  "versionStartIncluding": "6.2",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: avoid potential UAF in default_operstate()\n\nsyzbot reported an UAF in default_operstate() [1]\n\nIssue is a race between device and netns dismantles.\n\nAfter calling __rtnl_unlock() from netdev_run_todo(),\nwe can not assume the netns of each device is still alive.\n\nMake sure the device is not in NETREG_UNREGISTERED state,\nand add an ASSERT_RTNL() before the call to\n__dev_get_by_index().\n\nWe might move this ASSERT_RTNL() in __dev_get_by_index()\nin the future.\n\n[1]\n\nBUG: KASAN: slab-use-after-free in __dev_get_by_index+0x5d/0x110 net/core/dev.c:852\nRead of size 8 at addr ffff888043eba1b0 by task syz.0.0/5339\n\nCPU: 0 UID: 0 PID: 5339 Comm: syz.0.0 Not tainted 6.12.0-syzkaller-10296-gaaf20f870da0 #0\nHardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014\nCall Trace:\n \u003cTASK\u003e\n  __dump_stack lib/dump_stack.c:94 [inline]\n  dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120\n  print_address_description mm/kasan/report.c:378 [inline]\n  print_report+0x169/0x550 mm/kasan/report.c:489\n  kasan_report+0x143/0x180 mm/kasan/report.c:602\n  __dev_get_by_index+0x5d/0x110 net/core/dev.c:852\n  default_operstate net/core/link_watch.c:51 [inline]\n  rfc2863_policy+0x224/0x300 net/core/link_watch.c:67\n  linkwatch_do_dev+0x3e/0x170 net/core/link_watch.c:170\n  netdev_run_todo+0x461/0x1000 net/core/dev.c:10894\n  rtnl_unlock net/core/rtnetlink.c:152 [inline]\n  rtnl_net_unlock include/linux/rtnetlink.h:133 [inline]\n  rtnl_dellink+0x760/0x8d0 net/core/rtnetlink.c:3520\n  rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6911\n  netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2541\n  netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline]\n  netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1347\n  netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1891\n  sock_sendmsg_nosec net/socket.c:711 [inline]\n  __sock_sendmsg+0x221/0x270 net/socket.c:726\n  ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2583\n  ___sys_sendmsg net/socket.c:2637 [inline]\n  __sys_sendmsg+0x269/0x350 net/socket.c:2669\n  do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n  do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\nRIP: 0033:0x7f2a3cb80809\nCode: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 \u003c48\u003e 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48\nRSP: 002b:00007f2a3d9cd058 EFLAGS: 00000246 ORIG_RAX: 000000000000002e\nRAX: ffffffffffffffda RBX: 00007f2a3cd45fa0 RCX: 00007f2a3cb80809\nRDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000008\nRBP: 00007f2a3cbf393e R08: 0000000000000000 R09: 0000000000000000\nR10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000\nR13: 0000000000000000 R14: 00007f2a3cd45fa0 R15: 00007ffd03bc65c8\n \u003c/TASK\u003e\n\nAllocated by task 5339:\n  kasan_save_stack mm/kasan/common.c:47 [inline]\n  kasan_save_track+0x3f/0x80 mm/kasan/common.c:68\n  poison_kmalloc_redzone mm/kasan/common.c:377 [inline]\n  __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394\n  kasan_kmalloc include/linux/kasan.h:260 [inline]\n  __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4314\n  kmalloc_noprof include/linux/slab.h:901 [inline]\n  kmalloc_array_noprof include/linux/slab.h:945 [inline]\n  netdev_create_hash net/core/dev.c:11870 [inline]\n  netdev_init+0x10c/0x250 net/core/dev.c:11890\n  ops_init+0x31e/0x590 net/core/net_namespace.c:138\n  setup_net+0x287/0x9e0 net/core/net_namespace.c:362\n  copy_net_ns+0x33f/0x570 net/core/net_namespace.c:500\n  create_new_namespaces+0x425/0x7b0 kernel/nsproxy.c:110\n  unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228\n  ksys_unshare+0x57d/0xa70 kernel/fork.c:3314\n  __do_sys_unshare kernel/fork.c:3385 [inline]\n  __se_sys_unshare kernel/fork.c:3383 [inline]\n  __x64_sys_unshare+0x38/0x40 kernel/fork.c:3383\n  do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n  do_syscall_64+0xf3/0x230 arch/x8\n---truncated---"
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The vulnerability is reached through local syscalls only \u2014 `unshare(CLONE_NEWUSER|CLONE_NEWNET)` to create the namespace and an `RTM_DELLINK` rtnetlink message via `sendmsg()` on an `AF_NETLINK` socket. No network peer data is involved.\nAC:L - The attacker controls both sides of the race: they create and populate the netns, choose when to drop its last reference (triggering `cleanup_net`), and choose when to send RTM_DELLINK, and can retry the race in a loop indefinitely at no cost. syzbot reproduced it, and veth/vlan/macvlan satisfy the `iflink != ifindex` precondition in default configurations.\nPR:L - An unprivileged local user gets CAP_NET_ADMIN inside a new network namespace via `unshare -Urn`, which is exactly the path in the syzbot allocation trace (`ksys_unshare` \u2192 `copy_net_ns`), and that is sufficient to create veth devices and issue RTM_DELLINK.\nUI:N - The attacker performs all steps itself \u2014 namespace creation, device creation, link deletion, and namespace teardown \u2014 with no action required from any other user.\nS:U - The use-after-free occurs in kernel memory and its impact stays within the kernel\u0027s own security authority; no VM, IOMMU, or hypervisor boundary is crossed.\nC:H - This is a slab use-after-free read of a freed `kmalloc-2k` hash array whose contents the attacker can control via heap spray, turning the `hlist_for_each_entry()` walk into a controlled-pointer dereference; the resulting carrier bit is reflected into `dev-\u003eoperstate` and read back over netlink, yielding a kernel memory disclosure oracle.\nI:H - A use-after-free on a heavily reused general-purpose slab cache gives the attacker influence over the freed object contents and over which pointer the kernel follows and stores as `peer`, which is the standard basis for escalating to control-flow/state corruption.\nA:H - KASAN confirms a slab-use-after-free read, and walking the stale hash bucket dereferences reused or garbage pointers, causing a kernel oops or panic; the race can be retried repeatedly to force a crash."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T11:45:36.867Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/3265aab0736f78bb218200b06b1abb525c316269"
        },
        {
          "url": "https://git.kernel.org/stable/c/316183d58319f191e16503bc2dffa156c4442df2"
        },
        {
          "url": "https://git.kernel.org/stable/c/750e51603395e755537da08f745864c93e3ce741"
        }
      ],
      "title": "net: avoid potential UAF in default_operstate()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2024-56635",
    "datePublished": "2024-12-27T15:02:38.213Z",
    "dateReserved": "2024-12-27T15:00:39.838Z",
    "dateUpdated": "2026-08-05T11:45:36.867Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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CVE-2024-56635 (GCVE-0-2024-56635)

Tags

Sightings

Nomenclature

Related by attack behaviour