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CVE-2024-41040 (GCVE-0-2024-41040)

Vulnerability from cvelistv5 – Published: 2024-07-29 14:31 – Updated: 2026-08-05 11:34
VLAI
Title
net/sched: Fix UAF when resolving a clash
Summary
In the Linux kernel, the following vulnerability has been resolved: net/sched: Fix UAF when resolving a clash KASAN reports the following UAF: BUG: KASAN: slab-use-after-free in tcf_ct_flow_table_process_conn+0x12b/0x380 [act_ct] Read of size 1 at addr ffff888c07603600 by task handler130/6469 Call Trace: <IRQ> dump_stack_lvl+0x48/0x70 print_address_description.constprop.0+0x33/0x3d0 print_report+0xc0/0x2b0 kasan_report+0xd0/0x120 __asan_load1+0x6c/0x80 tcf_ct_flow_table_process_conn+0x12b/0x380 [act_ct] tcf_ct_act+0x886/0x1350 [act_ct] tcf_action_exec+0xf8/0x1f0 fl_classify+0x355/0x360 [cls_flower] __tcf_classify+0x1fd/0x330 tcf_classify+0x21c/0x3c0 sch_handle_ingress.constprop.0+0x2c5/0x500 __netif_receive_skb_core.constprop.0+0xb25/0x1510 __netif_receive_skb_list_core+0x220/0x4c0 netif_receive_skb_list_internal+0x446/0x620 napi_complete_done+0x157/0x3d0 gro_cell_poll+0xcf/0x100 __napi_poll+0x65/0x310 net_rx_action+0x30c/0x5c0 __do_softirq+0x14f/0x491 __irq_exit_rcu+0x82/0xc0 irq_exit_rcu+0xe/0x20 common_interrupt+0xa1/0xb0 </IRQ> <TASK> asm_common_interrupt+0x27/0x40 Allocated by task 6469: kasan_save_stack+0x38/0x70 kasan_set_track+0x25/0x40 kasan_save_alloc_info+0x1e/0x40 __kasan_krealloc+0x133/0x190 krealloc+0xaa/0x130 nf_ct_ext_add+0xed/0x230 [nf_conntrack] tcf_ct_act+0x1095/0x1350 [act_ct] tcf_action_exec+0xf8/0x1f0 fl_classify+0x355/0x360 [cls_flower] __tcf_classify+0x1fd/0x330 tcf_classify+0x21c/0x3c0 sch_handle_ingress.constprop.0+0x2c5/0x500 __netif_receive_skb_core.constprop.0+0xb25/0x1510 __netif_receive_skb_list_core+0x220/0x4c0 netif_receive_skb_list_internal+0x446/0x620 napi_complete_done+0x157/0x3d0 gro_cell_poll+0xcf/0x100 __napi_poll+0x65/0x310 net_rx_action+0x30c/0x5c0 __do_softirq+0x14f/0x491 Freed by task 6469: kasan_save_stack+0x38/0x70 kasan_set_track+0x25/0x40 kasan_save_free_info+0x2b/0x60 ____kasan_slab_free+0x180/0x1f0 __kasan_slab_free+0x12/0x30 slab_free_freelist_hook+0xd2/0x1a0 __kmem_cache_free+0x1a2/0x2f0 kfree+0x78/0x120 nf_conntrack_free+0x74/0x130 [nf_conntrack] nf_ct_destroy+0xb2/0x140 [nf_conntrack] __nf_ct_resolve_clash+0x529/0x5d0 [nf_conntrack] nf_ct_resolve_clash+0xf6/0x490 [nf_conntrack] __nf_conntrack_confirm+0x2c6/0x770 [nf_conntrack] tcf_ct_act+0x12ad/0x1350 [act_ct] tcf_action_exec+0xf8/0x1f0 fl_classify+0x355/0x360 [cls_flower] __tcf_classify+0x1fd/0x330 tcf_classify+0x21c/0x3c0 sch_handle_ingress.constprop.0+0x2c5/0x500 __netif_receive_skb_core.constprop.0+0xb25/0x1510 __netif_receive_skb_list_core+0x220/0x4c0 netif_receive_skb_list_internal+0x446/0x620 napi_complete_done+0x157/0x3d0 gro_cell_poll+0xcf/0x100 __napi_poll+0x65/0x310 net_rx_action+0x30c/0x5c0 __do_softirq+0x14f/0x491 The ct may be dropped if a clash has been resolved but is still passed to the tcf_ct_flow_table_process_conn function for further usage. This issue can be fixed by retrieving ct from skb again after confirming conntrack.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-09-10 16:23 UTC
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: f07c548314776231f0d47d73ec6caa5b17e876e8 , < b81a523d54ea689414f67c9fb81a5b917a41ed55 (git)
Affected: 0cc254e5aa37cf05f65bcdcdc0ac5c58010feb33 , < 2b4d68df3f57ea746c430941ba9c03d7d8b5a23f (git)
Affected: 0cc254e5aa37cf05f65bcdcdc0ac5c58010feb33 , < 4e71b10a100861fb27d9c5755dfd68f615629fae (git)
Affected: 0cc254e5aa37cf05f65bcdcdc0ac5c58010feb33 , < 799a34901b634008db4a7ece3900e2b971d4c932 (git)
Affected: 0cc254e5aa37cf05f65bcdcdc0ac5c58010feb33 , < ef472cc6693b16b202a916482df72f35d94bd69e (git)
Affected: 0cc254e5aa37cf05f65bcdcdc0ac5c58010feb33 , < 26488172b0292bed837b95a006a3f3431d1898c3 (git)
Affected: 30822781c89943b6a3ed122324ceb37cea7042a3 (git)
Affected: 5.10.43 , < 5.10.222 (semver)
Affected: 5.12.10 , < 5.13 (semver)
guessed Create a notification for this product.
Linux Linux Affected: 5.13
Unaffected: 0 , < 5.13 (semver)
Unaffected: 5.10.222 , ≤ 5.10.* (semver)
Unaffected: 5.15.163 , ≤ 5.15.* (semver)
Unaffected: 6.1.100 , ≤ 6.1.* (semver)
Unaffected: 6.6.41 , ≤ 6.6.* (semver)
Unaffected: 6.9.10 , ≤ 6.9.* (semver)
Unaffected: 6.10 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: Fix UAF when resolving a clash\n\nKASAN reports the following UAF:\n\n BUG: KASAN: slab-use-after-free in tcf_ct_flow_table_process_conn+0x12b/0x380 [act_ct]\n Read of size 1 at addr ffff888c07603600 by task handler130/6469\n\n Call Trace:\n  \u003cIRQ\u003e\n  dump_stack_lvl+0x48/0x70\n  print_address_description.constprop.0+0x33/0x3d0\n  print_report+0xc0/0x2b0\n  kasan_report+0xd0/0x120\n  __asan_load1+0x6c/0x80\n  tcf_ct_flow_table_process_conn+0x12b/0x380 [act_ct]\n  tcf_ct_act+0x886/0x1350 [act_ct]\n  tcf_action_exec+0xf8/0x1f0\n  fl_classify+0x355/0x360 [cls_flower]\n  __tcf_classify+0x1fd/0x330\n  tcf_classify+0x21c/0x3c0\n  sch_handle_ingress.constprop.0+0x2c5/0x500\n  __netif_receive_skb_core.constprop.0+0xb25/0x1510\n  __netif_receive_skb_list_core+0x220/0x4c0\n  netif_receive_skb_list_internal+0x446/0x620\n  napi_complete_done+0x157/0x3d0\n  gro_cell_poll+0xcf/0x100\n  __napi_poll+0x65/0x310\n  net_rx_action+0x30c/0x5c0\n  __do_softirq+0x14f/0x491\n  __irq_exit_rcu+0x82/0xc0\n  irq_exit_rcu+0xe/0x20\n  common_interrupt+0xa1/0xb0\n  \u003c/IRQ\u003e\n  \u003cTASK\u003e\n  asm_common_interrupt+0x27/0x40\n\n Allocated by task 6469:\n  kasan_save_stack+0x38/0x70\n  kasan_set_track+0x25/0x40\n  kasan_save_alloc_info+0x1e/0x40\n  __kasan_krealloc+0x133/0x190\n  krealloc+0xaa/0x130\n  nf_ct_ext_add+0xed/0x230 [nf_conntrack]\n  tcf_ct_act+0x1095/0x1350 [act_ct]\n  tcf_action_exec+0xf8/0x1f0\n  fl_classify+0x355/0x360 [cls_flower]\n  __tcf_classify+0x1fd/0x330\n  tcf_classify+0x21c/0x3c0\n  sch_handle_ingress.constprop.0+0x2c5/0x500\n  __netif_receive_skb_core.constprop.0+0xb25/0x1510\n  __netif_receive_skb_list_core+0x220/0x4c0\n  netif_receive_skb_list_internal+0x446/0x620\n  napi_complete_done+0x157/0x3d0\n  gro_cell_poll+0xcf/0x100\n  __napi_poll+0x65/0x310\n  net_rx_action+0x30c/0x5c0\n  __do_softirq+0x14f/0x491\n\n Freed by task 6469:\n  kasan_save_stack+0x38/0x70\n  kasan_set_track+0x25/0x40\n  kasan_save_free_info+0x2b/0x60\n  ____kasan_slab_free+0x180/0x1f0\n  __kasan_slab_free+0x12/0x30\n  slab_free_freelist_hook+0xd2/0x1a0\n  __kmem_cache_free+0x1a2/0x2f0\n  kfree+0x78/0x120\n  nf_conntrack_free+0x74/0x130 [nf_conntrack]\n  nf_ct_destroy+0xb2/0x140 [nf_conntrack]\n  __nf_ct_resolve_clash+0x529/0x5d0 [nf_conntrack]\n  nf_ct_resolve_clash+0xf6/0x490 [nf_conntrack]\n  __nf_conntrack_confirm+0x2c6/0x770 [nf_conntrack]\n  tcf_ct_act+0x12ad/0x1350 [act_ct]\n  tcf_action_exec+0xf8/0x1f0\n  fl_classify+0x355/0x360 [cls_flower]\n  __tcf_classify+0x1fd/0x330\n  tcf_classify+0x21c/0x3c0\n  sch_handle_ingress.constprop.0+0x2c5/0x500\n  __netif_receive_skb_core.constprop.0+0xb25/0x1510\n  __netif_receive_skb_list_core+0x220/0x4c0\n  netif_receive_skb_list_internal+0x446/0x620\n  napi_complete_done+0x157/0x3d0\n  gro_cell_poll+0xcf/0x100\n  __napi_poll+0x65/0x310\n  net_rx_action+0x30c/0x5c0\n  __do_softirq+0x14f/0x491\n\nThe ct may be dropped if a clash has been resolved but is still passed to\nthe tcf_ct_flow_table_process_conn function for further usage. This issue\ncan be fixed by retrieving ct from skb again after confirming conntrack."
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            "baseSeverity": "CRITICAL",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
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            {
              "lang": "en",
              "value": "AV:N - The vulnerable code executes in the NAPI receive softirq (`sch_handle_ingress` \u2192 `tcf_classify` \u2192 `tcf_ct_act`) on data taken directly from arriving packets, as the KASAN `\u003cIRQ\u003e`/`net_rx_action` trace shows. On any host configured with `action ct commit` (OVS-TC/OVN/Kubernetes offload nodes, the subsystem\u0027s primary deployment), an off-host attacker triggers it purely by sending routable UDP/ICMP/GRE traffic to or through the node.\nAC:L - The attacker controls both sides of the race by flooding packets with an identical 5-tuple, which RSS spreads across CPUs so two unconfirmed conntracks reach `nf_conntrack_confirm` concurrently \u2014 conntrack clashes on UDP bursts are so routine that the kernel has dedicated clash-resolution machinery and counters for them. Once a clash occurs the free of the loser ct and the subsequent stale dereference are deterministic.\nPR:N - Conntrack processing happens on ingress before any application-layer authentication or socket delivery, so the attacker needs no account, credentials, or local access on the target. The tc/act_ct configuration is established by the administrator as part of normal deployment, not by the attacker.\nUI:N - The UAF is triggered entirely by unsolicited inbound packets processed in softirq context; no local user or administrator has to open, mount, or interact with anything.\nS:U - The freed conntrack object, the corrupting writes, and the impacted flow-offload table all live within the same host kernel\u0027s security authority. No VM, IOMMU, or sandbox boundary is crossed.\nC:H - The freed `nf_ct_ext` is a plain kmalloc object that an attacker can reclaim and spray, and `nf_conn_act_ct_ext_find()` uses an attacker-controlled `u8` offset from it as a pointer offset, yielding a controlled out-of-bounds read whose result is written into the offload tuple. The dangling `nf_conn` is also read wholesale into the flow entry, exposing reclaimed kernel memory.\nI:H - `tcf_ct_flow_table_add()` writes into the freed object \u2014 `test_and_set_bit(IPS_OFFLOAD_BIT, \u0026ct-\u003estatus)`, `refcount_inc(\u0026ct-\u003ect_general.use)`, and `ct-\u003eproto.tcp.seen[].flags |=` \u2014 and persists `flow-\u003ect` as a dangling pointer in the flow-offload table. With the `nf_conn` slab (SLAB_TYPESAFE_BY_RCU) reclaimed by attacker-sprayed connections, this produces refcount confusion and later double-free/UAF on a live object, a classic path to control-flow hijack.\nA:H - The use-after-free reliably crashes the kernel in softirq context under KASAN or slab poisoning, and unpoisoned it corrupts conntrack refcounting and the flow-offload table, leading to oops or panic. The attacker can repeat the packet flood indefinitely to keep re-triggering it."
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    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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    "cveId": "CVE-2024-41040",
    "datePublished": "2024-07-29T14:31:53.853Z",
    "dateReserved": "2024-07-12T12:17:45.621Z",
    "dateUpdated": "2026-08-05T11:34:54.957Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2024-41040",
      "date": "2026-09-10",
      "epss": "0.01",
      "percentile": "0.60767"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2024-41040\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2024-07-29T15:15:12.473\",\"lastModified\":\"2026-08-04T11:19:21.393\",\"vulnStatus\":\"Modified\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nnet/sched: Fix UAF when resolving a clash\\n\\nKASAN reports the following UAF:\\n\\n BUG: KASAN: slab-use-after-free in tcf_ct_flow_table_process_conn+0x12b/0x380 [act_ct]\\n Read of size 1 at addr ffff888c07603600 by task handler130/6469\\n\\n Call Trace:\\n  \u003cIRQ\u003e\\n  dump_stack_lvl+0x48/0x70\\n  print_address_description.constprop.0+0x33/0x3d0\\n  print_report+0xc0/0x2b0\\n  kasan_report+0xd0/0x120\\n  __asan_load1+0x6c/0x80\\n  tcf_ct_flow_table_process_conn+0x12b/0x380 [act_ct]\\n  tcf_ct_act+0x886/0x1350 [act_ct]\\n  tcf_action_exec+0xf8/0x1f0\\n  fl_classify+0x355/0x360 [cls_flower]\\n  __tcf_classify+0x1fd/0x330\\n  tcf_classify+0x21c/0x3c0\\n  sch_handle_ingress.constprop.0+0x2c5/0x500\\n  __netif_receive_skb_core.constprop.0+0xb25/0x1510\\n  __netif_receive_skb_list_core+0x220/0x4c0\\n  netif_receive_skb_list_internal+0x446/0x620\\n  napi_complete_done+0x157/0x3d0\\n  gro_cell_poll+0xcf/0x100\\n  __napi_poll+0x65/0x310\\n  net_rx_action+0x30c/0x5c0\\n  __do_softirq+0x14f/0x491\\n  __irq_exit_rcu+0x82/0xc0\\n  irq_exit_rcu+0xe/0x20\\n  common_interrupt+0xa1/0xb0\\n  \u003c/IRQ\u003e\\n  \u003cTASK\u003e\\n  asm_common_interrupt+0x27/0x40\\n\\n Allocated by task 6469:\\n  kasan_save_stack+0x38/0x70\\n  kasan_set_track+0x25/0x40\\n  kasan_save_alloc_info+0x1e/0x40\\n  __kasan_krealloc+0x133/0x190\\n  krealloc+0xaa/0x130\\n  nf_ct_ext_add+0xed/0x230 [nf_conntrack]\\n  tcf_ct_act+0x1095/0x1350 [act_ct]\\n  tcf_action_exec+0xf8/0x1f0\\n  fl_classify+0x355/0x360 [cls_flower]\\n  __tcf_classify+0x1fd/0x330\\n  tcf_classify+0x21c/0x3c0\\n  sch_handle_ingress.constprop.0+0x2c5/0x500\\n  __netif_receive_skb_core.constprop.0+0xb25/0x1510\\n  __netif_receive_skb_list_core+0x220/0x4c0\\n  netif_receive_skb_list_internal+0x446/0x620\\n  napi_complete_done+0x157/0x3d0\\n  gro_cell_poll+0xcf/0x100\\n  __napi_poll+0x65/0x310\\n  net_rx_action+0x30c/0x5c0\\n  __do_softirq+0x14f/0x491\\n\\n Freed by task 6469:\\n  kasan_save_stack+0x38/0x70\\n  kasan_set_track+0x25/0x40\\n  kasan_save_free_info+0x2b/0x60\\n  ____kasan_slab_free+0x180/0x1f0\\n  __kasan_slab_free+0x12/0x30\\n  slab_free_freelist_hook+0xd2/0x1a0\\n  __kmem_cache_free+0x1a2/0x2f0\\n  kfree+0x78/0x120\\n  nf_conntrack_free+0x74/0x130 [nf_conntrack]\\n  nf_ct_destroy+0xb2/0x140 [nf_conntrack]\\n  __nf_ct_resolve_clash+0x529/0x5d0 [nf_conntrack]\\n  nf_ct_resolve_clash+0xf6/0x490 [nf_conntrack]\\n  __nf_conntrack_confirm+0x2c6/0x770 [nf_conntrack]\\n  tcf_ct_act+0x12ad/0x1350 [act_ct]\\n  tcf_action_exec+0xf8/0x1f0\\n  fl_classify+0x355/0x360 [cls_flower]\\n  __tcf_classify+0x1fd/0x330\\n  tcf_classify+0x21c/0x3c0\\n  sch_handle_ingress.constprop.0+0x2c5/0x500\\n  __netif_receive_skb_core.constprop.0+0xb25/0x1510\\n  __netif_receive_skb_list_core+0x220/0x4c0\\n  netif_receive_skb_list_internal+0x446/0x620\\n  napi_complete_done+0x157/0x3d0\\n  gro_cell_poll+0xcf/0x100\\n  __napi_poll+0x65/0x310\\n  net_rx_action+0x30c/0x5c0\\n  __do_softirq+0x14f/0x491\\n\\nThe ct may be dropped if a clash has been resolved but is still passed to\\nthe tcf_ct_flow_table_process_conn function for further usage. This issue\\ncan be fixed by retrieving ct from skb again after confirming conntrack.\"},{\"lang\":\"es\",\"value\":\"En el kernel de Linux se ha resuelto la siguiente vulnerabilidad: net/sched: Reparar UAF al resolver un conflicto KASAN reporta el siguiente UAF: ERROR: KASAN: slab-use-after-free en tcf_ct_flow_table_process_conn+0x12b/0x380 [act_ct] Lectura de tama\u00f1o 1 en la direcci\u00f3n ffff888c07603600 por el controlador de tareas 130/6469 Seguimiento de llamadas:  dump_stack_lvl+0x48/0x70 print_address_description.constprop.0+0x33/0x3d0 print_report+0xc0/0x2b0 kasan_report+0xd0/0x120 __asan_load1+0x 6c/0x80 tcf_ct_flow_table_process_conn+0x12b/0x380 [act_ct] tcf_ct_act+0x886/0x1350 [act_ct] tcf_action_exec+0xf8/0x1f0 fl_classify+0x355/0x360 [cls_flower] __tcf_classify+0x1fd/0x330 tcf_classify+0x21c/0x3c0 sch_handle_ingress.constprop.0+0x 2c5/0x500 __netif_receive_skb_core.constprop.0+0xb25 /0x1510 __netif_receive_skb_list_core+0x220/0x4c0 netif_receive_skb_list_internal+0x446/0x620 napi_complete_done+0x157/0x3d0 gro_cell_poll+0xcf/0x100 __napi_poll+0x65/0x310 net_rx_action+0x30 c/0x5c0 __do_softirq+0x14f/0x491 __irq_exit_rcu+0x82/0xc0 irq_exit_rcu+0xe/0x20 common_interrupt+0xa1 /0xb0   asm_common_interrupt+0x27/0x40 Asignado por la tarea 6469: kasan_save_stack+0x38/0x70 kasan_set_track+0x25/0x40 kasan_save_alloc_info+0x1e/0x40 __kasan_krealloc+0x133/0x190 a/0x130 nf_ct_ext_add+0xed/0x230 [ nf_conntrack] tcf_ct_act+0x1095/0x1350 [act_ct] tcf_action_exec+0xf8/0x1f0 fl_classify+0x355/0x360 [cls_flower] __tcf_classify+0x1fd/0x330 tcf_classify+0x21c/0x3c0 sch_handle_ingress.constprop. 0+0x2c5/0x500 __netif_receive_skb_core.constprop.0+0xb25/ 0x1510 __netif_receive_skb_list_core+0x220/0x4c0 netif_receive_skb_list_internal+0x446/0x620 napi_complete_done+0x157/0x3d0 gro_cell_poll+0xcf/0x100 __napi_poll+0x65/0x310 net_rx_action+0x30 c/0x5c0 __do_softirq+0x14f/0x491 Liberado por la tarea 6469: kasan_save_stack+0x38/0x70 kasan_set_track+0x25/ 0x40 kasan_save_free_info+0x2b/0x60 ____kasan_slab_free+0x180/0x1f0 __kasan_slab_free+0x12/0x30 slab_free_freelist_hook+0xd2/0x1a0 __kmem_cache_free+0x1a2/0x2f0 kfree+0x78/0x120 conntrack_free+0x74/0x130 [nf_conntrack] nf_ct_destroy+0xb2/0x140 [nf_conntrack] __nf_ct_resolve_clash+0x529 /0x5d0 [nf_conntrack] nf_ct_resolve_clash+0xf6/0x490 [nf_conntrack] __nf_conntrack_confirm+0x2c6/0x770 [nf_conntrack] tcf_ct_act+0x12ad/0x1350 [act_ct] tcf_action_exec+0xf8/0x1f0 x355/0x360 [cls_flower] __tcf_classify+0x1fd/0x330 tcf_classify+0x21c /0x3c0 sch_handle_ingress.constprop.0+0x2c5/0x500 __netif_receive_skb_core.constprop.0+0xb25/0x1510 __netif_receive_skb_list_core+0x220/0x4c0 netif_receive_skb_list_internal+0x446/0x620 napi_complete_ done+0x157/0x3d0 gro_cell_poll+0xcf/0x100 __napi_poll+0x65/0x310 net_rx_action+0x30c/0x5c0 __do_softirq+0x14f/0x491 El ct se puede descartar si se resolvi\u00f3 un conflicto pero a\u00fan se pasa a la funci\u00f3n tcf_ct_flow_table_process_conn para su uso posterior. Este problema se puede solucionar recuperando ct de skb nuevamente despu\u00e9s de confirmar conntrack.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"net/sched/act_ct.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"f07c548314776231f0d47d73ec6caa5b17e876e8\",\"lessThan\":\"b81a523d54ea689414f67c9fb81a5b917a41ed55\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"0cc254e5aa37cf05f65bcdcdc0ac5c58010feb33\",\"lessThan\":\"2b4d68df3f57ea746c430941ba9c03d7d8b5a23f\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"0cc254e5aa37cf05f65bcdcdc0ac5c58010feb33\",\"lessThan\":\"4e71b10a100861fb27d9c5755dfd68f615629fae\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"0cc254e5aa37cf05f65bcdcdc0ac5c58010feb33\",\"lessThan\":\"799a34901b634008db4a7ece3900e2b971d4c932\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"0cc254e5aa37cf05f65bcdcdc0ac5c58010feb33\",\"lessThan\":\"ef472cc6693b16b202a916482df72f35d94bd69e\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"0cc254e5aa37cf05f65bcdcdc0ac5c58010feb33\",\"lessThan\":\"26488172b0292bed837b95a006a3f3431d1898c3\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"30822781c89943b6a3ed122324ceb37cea7042a3\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"5.10.43\",\"lessThan\":\"5.10.222\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"5.12.10\",\"lessThan\":\"5.13\",\"versionType\":\"semver\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"net/sched/act_ct.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"5.13\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"5.13\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.10.222\",\"lessThanOrEqual\":\"5.10.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.15.163\",\"lessThanOrEqual\":\"5.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.100\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.41\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.9.10\",\"lessThanOrEqual\":\"6.9.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.10\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":9.8,\"baseSeverity\":\"CRITICAL\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":3.9,\"impactScore\":5.9},{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":7.0,\"baseSeverity\":\"HIGH\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"HIGH\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.0,\"impactScore\":5.9}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2024-09-10T16:23:16.958477Z\",\"id\":\"CVE-2024-41040\",\"options\":[{\"exploitation\":\"none\"},{\"automatable\":\"no\"},{\"technicalImpact\":\"partial\"}],\"role\":\"CISA Coordinator\",\"version\":\"2.0.3\"}}]},\"weaknesses\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-416\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.10.43\",\"versionEndExcluding\":\"5.10.222\",\"matchCriteriaId\":\"F2B53B37-EB61-42A6-B025-6E7F22431918\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.12.10\",\"versionEndExcluding\":\"5.13\",\"matchCriteriaId\":\"EE9935B9-8F11-4DF6-83D0-CE5ADC82165C\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.13\",\"versionEndExcluding\":\"5.15.163\",\"matchCriteriaId\":\"31C44972-374E-4ACF-9BAD-D5A04C707D45\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.16\",\"versionEndExcluding\":\"6.1.100\",\"matchCriteriaId\":\"100CDF74-4DB5-4FC6-A54B-BDBDB0C27137\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.2\",\"versionEndExcluding\":\"6.6.41\",\"matchCriteriaId\":\"96AC42B8-D66D-4AC5-B466-E9BA7910FA29\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.7\",\"versionEndExcluding\":\"6.9.10\",\"matchCriteriaId\":\"AB2E8DEC-CFD5-4C2B-981D-E7E45A36C352\"}]}]}],\"references\":[{\"url\":\"https://git.kernel.org/stable/c/26488172b0292bed837b95a006a3f3431d1898c3\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/2b4d68df3f57ea746c430941ba9c03d7d8b5a23f\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/4e71b10a100861fb27d9c5755dfd68f615629fae\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/799a34901b634008db4a7ece3900e2b971d4c932\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/b81a523d54ea689414f67c9fb81a5b917a41ed55\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/ef472cc6693b16b202a916482df72f35d94bd69e\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/26488172b0292bed837b95a006a3f3431d1898c3\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/2b4d68df3f57ea746c430941ba9c03d7d8b5a23f\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/4e71b10a100861fb27d9c5755dfd68f615629fae\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/799a34901b634008db4a7ece3900e2b971d4c932\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/b81a523d54ea689414f67c9fb81a5b917a41ed55\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/ef472cc6693b16b202a916482df72f35d94bd69e\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Patch\"]},{\"url\":\"https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-08-04T18:37:44+00:00",
      "cve": "CVE-2024-41040",
      "id": "CVE-2024-41040",
      "initial_release_date": "2024-07-29T00:00:00+00:00",
      "product_status:fixed": "783",
      "product_status:known_affected": "22",
      "product_status:known_not_affected": "43",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: net/sched: Fix UAF when resolving a clash",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2024/cve-2024-41040.json",
      "version": "3"
    },
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CVE Program Container\", \"references\": [{\"url\": \"https://git.kernel.org/stable/c/b81a523d54ea689414f67c9fb81a5b917a41ed55\", \"tags\": [\"x_transferred\"]}, {\"url\": \"https://git.kernel.org/stable/c/2b4d68df3f57ea746c430941ba9c03d7d8b5a23f\", \"tags\": [\"x_transferred\"]}, {\"url\": \"https://git.kernel.org/stable/c/4e71b10a100861fb27d9c5755dfd68f615629fae\", \"tags\": [\"x_transferred\"]}, {\"url\": \"https://git.kernel.org/stable/c/799a34901b634008db4a7ece3900e2b971d4c932\", \"tags\": [\"x_transferred\"]}, {\"url\": \"https://git.kernel.org/stable/c/ef472cc6693b16b202a916482df72f35d94bd69e\", \"tags\": [\"x_transferred\"]}, {\"url\": \"https://git.kernel.org/stable/c/26488172b0292bed837b95a006a3f3431d1898c3\", \"tags\": [\"x_transferred\"]}, {\"url\": \"https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html\"}], \"providerMetadata\": {\"orgId\": \"af854a3a-2127-422b-91ae-364da2661108\", \"shortName\": \"CVE\", \"dateUpdated\": \"2025-11-03T21:59:38.071Z\"}}, {\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2024-41040\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2024-09-10T16:23:16.958477Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2024-09-11T12:42:20.356Z\"}}], \"cna\": {\"title\": \"net/sched: Fix UAF when resolving a clash\", \"metrics\": [{\"cvssV3_1\": {\"version\": \"3.1\", \"baseScore\": 9.8, \"baseSeverity\": \"CRITICAL\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"AV:N - The vulnerable code executes in the NAPI receive softirq (`sch_handle_ingress` \\u2192 `tcf_classify` \\u2192 `tcf_ct_act`) on data taken directly from arriving packets, as the KASAN `\u003cIRQ\u003e`/`net_rx_action` trace shows. On any host configured with `action ct commit` (OVS-TC/OVN/Kubernetes offload nodes, the subsystem\u0027s primary deployment), an off-host attacker triggers it purely by sending routable UDP/ICMP/GRE traffic to or through the node.\\nAC:L - The attacker controls both sides of the race by flooding packets with an identical 5-tuple, which RSS spreads across CPUs so two unconfirmed conntracks reach `nf_conntrack_confirm` concurrently \\u2014 conntrack clashes on UDP bursts are so routine that the kernel has dedicated clash-resolution machinery and counters for them. Once a clash occurs the free of the loser ct and the subsequent stale dereference are deterministic.\\nPR:N - Conntrack processing happens on ingress before any application-layer authentication or socket delivery, so the attacker needs no account, credentials, or local access on the target. The tc/act_ct configuration is established by the administrator as part of normal deployment, not by the attacker.\\nUI:N - The UAF is triggered entirely by unsolicited inbound packets processed in softirq context; no local user or administrator has to open, mount, or interact with anything.\\nS:U - The freed conntrack object, the corrupting writes, and the impacted flow-offload table all live within the same host kernel\u0027s security authority. No VM, IOMMU, or sandbox boundary is crossed.\\nC:H - The freed `nf_ct_ext` is a plain kmalloc object that an attacker can reclaim and spray, and `nf_conn_act_ct_ext_find()` uses an attacker-controlled `u8` offset from it as a pointer offset, yielding a controlled out-of-bounds read whose result is written into the offload tuple. The dangling `nf_conn` is also read wholesale into the flow entry, exposing reclaimed kernel memory.\\nI:H - `tcf_ct_flow_table_add()` writes into the freed object \\u2014 `test_and_set_bit(IPS_OFFLOAD_BIT, \u0026ct-\u003estatus)`, `refcount_inc(\u0026ct-\u003ect_general.use)`, and `ct-\u003eproto.tcp.seen[].flags |=` \\u2014 and persists `flow-\u003ect` as a dangling pointer in the flow-offload table. With the `nf_conn` slab (SLAB_TYPESAFE_BY_RCU) reclaimed by attacker-sprayed connections, this produces refcount confusion and later double-free/UAF on a live object, a classic path to control-flow hijack.\\nA:H - The use-after-free reliably crashes the kernel in softirq context under KASAN or slab poisoning, and unpoisoned it corrupts conntrack refcounting and the flow-offload table, leading to oops or panic. The attacker can repeat the packet flood indefinitely to keep re-triggering it.\"}]}], \"affected\": [{\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"f07c548314776231f0d47d73ec6caa5b17e876e8\", \"lessThan\": \"b81a523d54ea689414f67c9fb81a5b917a41ed55\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"0cc254e5aa37cf05f65bcdcdc0ac5c58010feb33\", \"lessThan\": \"2b4d68df3f57ea746c430941ba9c03d7d8b5a23f\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"0cc254e5aa37cf05f65bcdcdc0ac5c58010feb33\", \"lessThan\": \"4e71b10a100861fb27d9c5755dfd68f615629fae\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"0cc254e5aa37cf05f65bcdcdc0ac5c58010feb33\", \"lessThan\": \"799a34901b634008db4a7ece3900e2b971d4c932\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"0cc254e5aa37cf05f65bcdcdc0ac5c58010feb33\", \"lessThan\": \"ef472cc6693b16b202a916482df72f35d94bd69e\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"0cc254e5aa37cf05f65bcdcdc0ac5c58010feb33\", \"lessThan\": \"26488172b0292bed837b95a006a3f3431d1898c3\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"30822781c89943b6a3ed122324ceb37cea7042a3\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"5.10.43\", \"lessThan\": \"5.10.222\", \"versionType\": \"semver\"}, {\"status\": \"affected\", \"version\": \"5.12.10\", \"lessThan\": \"5.13\", \"versionType\": \"semver\"}], \"programFiles\": [\"net/sched/act_ct.c\"], \"defaultStatus\": \"unaffected\"}, {\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"5.13\"}, {\"status\": \"unaffected\", \"version\": \"0\", \"lessThan\": \"5.13\", \"versionType\": \"semver\"}, {\"status\": \"unaffected\", \"version\": \"5.10.222\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"5.10.*\"}, {\"status\": \"unaffected\", \"version\": \"5.15.163\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"5.15.*\"}, {\"status\": \"unaffected\", \"version\": \"6.1.100\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.1.*\"}, {\"status\": \"unaffected\", \"version\": \"6.6.41\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.6.*\"}, {\"status\": \"unaffected\", \"version\": \"6.9.10\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.9.*\"}, {\"status\": \"unaffected\", \"version\": \"6.10\", \"versionType\": \"original_commit_for_fix\", \"lessThanOrEqual\": \"*\"}], \"programFiles\": [\"net/sched/act_ct.c\"], \"defaultStatus\": \"affected\"}], \"references\": [{\"url\": \"https://git.kernel.org/stable/c/b81a523d54ea689414f67c9fb81a5b917a41ed55\"}, {\"url\": \"https://git.kernel.org/stable/c/2b4d68df3f57ea746c430941ba9c03d7d8b5a23f\"}, {\"url\": \"https://git.kernel.org/stable/c/4e71b10a100861fb27d9c5755dfd68f615629fae\"}, {\"url\": \"https://git.kernel.org/stable/c/799a34901b634008db4a7ece3900e2b971d4c932\"}, {\"url\": \"https://git.kernel.org/stable/c/ef472cc6693b16b202a916482df72f35d94bd69e\"}, {\"url\": \"https://git.kernel.org/stable/c/26488172b0292bed837b95a006a3f3431d1898c3\"}], \"x_generator\": {\"engine\": \"bippy-1.2.0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"In the Linux kernel, the following vulnerability has been resolved:\\n\\nnet/sched: Fix UAF when resolving a clash\\n\\nKASAN reports the following UAF:\\n\\n BUG: KASAN: slab-use-after-free in tcf_ct_flow_table_process_conn+0x12b/0x380 [act_ct]\\n Read of size 1 at addr ffff888c07603600 by task handler130/6469\\n\\n Call Trace:\\n  \u003cIRQ\u003e\\n  dump_stack_lvl+0x48/0x70\\n  print_address_description.constprop.0+0x33/0x3d0\\n  print_report+0xc0/0x2b0\\n  kasan_report+0xd0/0x120\\n  __asan_load1+0x6c/0x80\\n  tcf_ct_flow_table_process_conn+0x12b/0x380 [act_ct]\\n  tcf_ct_act+0x886/0x1350 [act_ct]\\n  tcf_action_exec+0xf8/0x1f0\\n  fl_classify+0x355/0x360 [cls_flower]\\n  __tcf_classify+0x1fd/0x330\\n  tcf_classify+0x21c/0x3c0\\n  sch_handle_ingress.constprop.0+0x2c5/0x500\\n  __netif_receive_skb_core.constprop.0+0xb25/0x1510\\n  __netif_receive_skb_list_core+0x220/0x4c0\\n  netif_receive_skb_list_internal+0x446/0x620\\n  napi_complete_done+0x157/0x3d0\\n  gro_cell_poll+0xcf/0x100\\n  __napi_poll+0x65/0x310\\n  net_rx_action+0x30c/0x5c0\\n  __do_softirq+0x14f/0x491\\n  __irq_exit_rcu+0x82/0xc0\\n  irq_exit_rcu+0xe/0x20\\n  common_interrupt+0xa1/0xb0\\n  \u003c/IRQ\u003e\\n  \u003cTASK\u003e\\n  asm_common_interrupt+0x27/0x40\\n\\n Allocated by task 6469:\\n  kasan_save_stack+0x38/0x70\\n  kasan_set_track+0x25/0x40\\n  kasan_save_alloc_info+0x1e/0x40\\n  __kasan_krealloc+0x133/0x190\\n  krealloc+0xaa/0x130\\n  nf_ct_ext_add+0xed/0x230 [nf_conntrack]\\n  tcf_ct_act+0x1095/0x1350 [act_ct]\\n  tcf_action_exec+0xf8/0x1f0\\n  fl_classify+0x355/0x360 [cls_flower]\\n  __tcf_classify+0x1fd/0x330\\n  tcf_classify+0x21c/0x3c0\\n  sch_handle_ingress.constprop.0+0x2c5/0x500\\n  __netif_receive_skb_core.constprop.0+0xb25/0x1510\\n  __netif_receive_skb_list_core+0x220/0x4c0\\n  netif_receive_skb_list_internal+0x446/0x620\\n  napi_complete_done+0x157/0x3d0\\n  gro_cell_poll+0xcf/0x100\\n  __napi_poll+0x65/0x310\\n  net_rx_action+0x30c/0x5c0\\n  __do_softirq+0x14f/0x491\\n\\n Freed by task 6469:\\n  kasan_save_stack+0x38/0x70\\n  kasan_set_track+0x25/0x40\\n  kasan_save_free_info+0x2b/0x60\\n  ____kasan_slab_free+0x180/0x1f0\\n  __kasan_slab_free+0x12/0x30\\n  slab_free_freelist_hook+0xd2/0x1a0\\n  __kmem_cache_free+0x1a2/0x2f0\\n  kfree+0x78/0x120\\n  nf_conntrack_free+0x74/0x130 [nf_conntrack]\\n  nf_ct_destroy+0xb2/0x140 [nf_conntrack]\\n  __nf_ct_resolve_clash+0x529/0x5d0 [nf_conntrack]\\n  nf_ct_resolve_clash+0xf6/0x490 [nf_conntrack]\\n  __nf_conntrack_confirm+0x2c6/0x770 [nf_conntrack]\\n  tcf_ct_act+0x12ad/0x1350 [act_ct]\\n  tcf_action_exec+0xf8/0x1f0\\n  fl_classify+0x355/0x360 [cls_flower]\\n  __tcf_classify+0x1fd/0x330\\n  tcf_classify+0x21c/0x3c0\\n  sch_handle_ingress.constprop.0+0x2c5/0x500\\n  __netif_receive_skb_core.constprop.0+0xb25/0x1510\\n  __netif_receive_skb_list_core+0x220/0x4c0\\n  netif_receive_skb_list_internal+0x446/0x620\\n  napi_complete_done+0x157/0x3d0\\n  gro_cell_poll+0xcf/0x100\\n  __napi_poll+0x65/0x310\\n  net_rx_action+0x30c/0x5c0\\n  __do_softirq+0x14f/0x491\\n\\nThe ct may be dropped if a clash has been resolved but is still passed to\\nthe tcf_ct_flow_table_process_conn function for further usage. This issue\\ncan be fixed by retrieving ct from skb again after confirming conntrack.\"}], \"cpeApplicability\": [{\"nodes\": [{\"negate\": false, \"cpeMatch\": [{\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"5.10.222\", \"versionStartIncluding\": \"5.10.43\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"5.15.163\", \"versionStartIncluding\": \"5.13\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.1.100\", \"versionStartIncluding\": \"5.13\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.6.41\", \"versionStartIncluding\": \"5.13\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.9.10\", \"versionStartIncluding\": \"5.13\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.10\", \"versionStartIncluding\": \"5.13\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionStartIncluding\": \"5.12.10\"}], \"operator\": \"OR\"}]}], \"providerMetadata\": {\"orgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"shortName\": \"Linux\", \"dateUpdated\": \"2026-08-05T11:34:54.957Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2024-41040\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-08-05T11:34:54.957Z\", \"dateReserved\": \"2024-07-12T12:17:45.621Z\", \"assignerOrgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"datePublished\": \"2024-07-29T14:31:53.853Z\", \"assignerShortName\": \"Linux\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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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.


Detection rules are retrieved from Rulezet.