CVE-2021-47606 (GCVE-0-2021-47606)

Vulnerability from cvelistv5 – Published: 2024-06-19 14:54 – Updated: 2026-05-11 13:57
VLAI
Title
net: netlink: af_netlink: Prevent empty skb by adding a check on len.
Summary
In the Linux kernel, the following vulnerability has been resolved: net: netlink: af_netlink: Prevent empty skb by adding a check on len. Adding a check on len parameter to avoid empty skb. This prevents a division error in netem_enqueue function which is caused when skb->len=0 and skb->data_len=0 in the randomized corruption step as shown below. skb->data[prandom_u32() % skb_headlen(skb)] ^= 1<<(prandom_u32() % 8); Crash Report: [ 343.170349] netdevsim netdevsim0 netdevsim3: set [1, 0] type 2 family 0 port 6081 - 0 [ 343.216110] netem: version 1.3 [ 343.235841] divide error: 0000 [#1] PREEMPT SMP KASAN NOPTI [ 343.236680] CPU: 3 PID: 4288 Comm: reproducer Not tainted 5.16.0-rc1+ [ 343.237569] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014 [ 343.238707] RIP: 0010:netem_enqueue+0x1590/0x33c0 [sch_netem] [ 343.239499] Code: 89 85 58 ff ff ff e8 5f 5d e9 d3 48 8b b5 48 ff ff ff 8b 8d 50 ff ff ff 8b 85 58 ff ff ff 48 8b bd 70 ff ff ff 31 d2 2b 4f 74 <f7> f1 48 b8 00 00 00 00 00 fc ff df 49 01 d5 4c 89 e9 48 c1 e9 03 [ 343.241883] RSP: 0018:ffff88800bcd7368 EFLAGS: 00010246 [ 343.242589] RAX: 00000000ba7c0a9c RBX: 0000000000000001 RCX: 0000000000000000 [ 343.243542] RDX: 0000000000000000 RSI: ffff88800f8edb10 RDI: ffff88800f8eda40 [ 343.244474] RBP: ffff88800bcd7458 R08: 0000000000000000 R09: ffffffff94fb8445 [ 343.245403] R10: ffffffff94fb8336 R11: ffffffff94fb8445 R12: 0000000000000000 [ 343.246355] R13: ffff88800a5a7000 R14: ffff88800a5b5800 R15: 0000000000000020 [ 343.247291] FS: 00007fdde2bd7700(0000) GS:ffff888109780000(0000) knlGS:0000000000000000 [ 343.248350] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 343.249120] CR2: 00000000200000c0 CR3: 000000000ef4c000 CR4: 00000000000006e0 [ 343.250076] Call Trace: [ 343.250423] <TASK> [ 343.250713] ? memcpy+0x4d/0x60 [ 343.251162] ? netem_init+0xa0/0xa0 [sch_netem] [ 343.251795] ? __sanitizer_cov_trace_pc+0x21/0x60 [ 343.252443] netem_enqueue+0xe28/0x33c0 [sch_netem] [ 343.253102] ? stack_trace_save+0x87/0xb0 [ 343.253655] ? filter_irq_stacks+0xb0/0xb0 [ 343.254220] ? netem_init+0xa0/0xa0 [sch_netem] [ 343.254837] ? __kasan_check_write+0x14/0x20 [ 343.255418] ? _raw_spin_lock+0x88/0xd6 [ 343.255953] dev_qdisc_enqueue+0x50/0x180 [ 343.256508] __dev_queue_xmit+0x1a7e/0x3090 [ 343.257083] ? netdev_core_pick_tx+0x300/0x300 [ 343.257690] ? check_kcov_mode+0x10/0x40 [ 343.258219] ? _raw_spin_unlock_irqrestore+0x29/0x40 [ 343.258899] ? __kasan_init_slab_obj+0x24/0x30 [ 343.259529] ? setup_object.isra.71+0x23/0x90 [ 343.260121] ? new_slab+0x26e/0x4b0 [ 343.260609] ? kasan_poison+0x3a/0x50 [ 343.261118] ? kasan_unpoison+0x28/0x50 [ 343.261637] ? __kasan_slab_alloc+0x71/0x90 [ 343.262214] ? memcpy+0x4d/0x60 [ 343.262674] ? write_comp_data+0x2f/0x90 [ 343.263209] ? __kasan_check_write+0x14/0x20 [ 343.263802] ? __skb_clone+0x5d6/0x840 [ 343.264329] ? __sanitizer_cov_trace_pc+0x21/0x60 [ 343.264958] dev_queue_xmit+0x1c/0x20 [ 343.265470] netlink_deliver_tap+0x652/0x9c0 [ 343.266067] netlink_unicast+0x5a0/0x7f0 [ 343.266608] ? netlink_attachskb+0x860/0x860 [ 343.267183] ? __sanitizer_cov_trace_pc+0x21/0x60 [ 343.267820] ? write_comp_data+0x2f/0x90 [ 343.268367] netlink_sendmsg+0x922/0xe80 [ 343.268899] ? netlink_unicast+0x7f0/0x7f0 [ 343.269472] ? __sanitizer_cov_trace_pc+0x21/0x60 [ 343.270099] ? write_comp_data+0x2f/0x90 [ 343.270644] ? netlink_unicast+0x7f0/0x7f0 [ 343.271210] sock_sendmsg+0x155/0x190 [ 343.271721] ____sys_sendmsg+0x75f/0x8f0 [ 343.272262] ? kernel_sendmsg+0x60/0x60 [ 343.272788] ? write_comp_data+0x2f/0x90 [ 343.273332] ? write_comp_data+0x2f/0x90 [ 343.273869] ___sys_sendmsg+0x10f/0x190 [ 343.274405] ? sendmsg_copy_msghdr+0x80/0x80 [ 343.274984] ? slab_post_alloc_hook+0x70/0x230 [ 343.275597] ? futex_wait_setup+0x240/0x240 [ 343.276175] ? security_file_alloc+0x3e/0x170 [ 343.276779] ? write_comp_d ---truncated---
Severity
No CVSS data available.
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-09-10 17:12 UTC
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: bcbde0d449eda7afa8f63280b165c8300dbd00e2 , < c54a60c8fbaa774f828e26df79f66229a8a0e010 (git)
Affected: bcbde0d449eda7afa8f63280b165c8300dbd00e2 , < 40cf2e058832d9cfaae98dfd77334926275598b6 (git)
Affected: bcbde0d449eda7afa8f63280b165c8300dbd00e2 , < 54e785f7d5c197bc06dbb8053700df7e2a093ced (git)
Affected: bcbde0d449eda7afa8f63280b165c8300dbd00e2 , < ff3f517bf7138e01a17369042908a3f345c0ee41 (git)
Affected: bcbde0d449eda7afa8f63280b165c8300dbd00e2 , < c0315e93552e0d840e9edc6abd71c7db82ec8f51 (git)
Affected: bcbde0d449eda7afa8f63280b165c8300dbd00e2 , < dadce61247c6230489527cc5e343b6002d1114c5 (git)
Affected: bcbde0d449eda7afa8f63280b165c8300dbd00e2 , < 4c986072a8c9249b9398c7a18f216dc26a9f0e35 (git)
Affected: bcbde0d449eda7afa8f63280b165c8300dbd00e2 , < f123cffdd8fe8ea6c7fded4b88516a42798797d0 (git)
Create a notification for this product.
Linux Linux Affected: 3.11
Unaffected: 0 , < 3.11 (semver)
Unaffected: 4.4.296 , ≤ 4.4.* (semver)
Unaffected: 4.9.294 , ≤ 4.9.* (semver)
Unaffected: 4.14.259 , ≤ 4.14.* (semver)
Unaffected: 4.19.222 , ≤ 4.19.* (semver)
Unaffected: 5.4.167 , ≤ 5.4.* (semver)
Unaffected: 5.10.87 , ≤ 5.10.* (semver)
Unaffected: 5.15.10 , ≤ 5.15.* (semver)
Unaffected: 5.16 , ≤ * (original_commit_for_fix)
Create a notification for this product.
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      "descriptions": [
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          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: netlink: af_netlink: Prevent empty skb by adding a check on len.\n\nAdding a check on len parameter to avoid empty skb. This prevents a\ndivision error in netem_enqueue function which is caused when skb-\u003elen=0\nand skb-\u003edata_len=0 in the randomized corruption step as shown below.\n\nskb-\u003edata[prandom_u32() % skb_headlen(skb)] ^= 1\u003c\u003c(prandom_u32() % 8);\n\nCrash Report:\n[  343.170349] netdevsim netdevsim0 netdevsim3: set [1, 0] type 2 family\n0 port 6081 - 0\n[  343.216110] netem: version 1.3\n[  343.235841] divide error: 0000 [#1] PREEMPT SMP KASAN NOPTI\n[  343.236680] CPU: 3 PID: 4288 Comm: reproducer Not tainted 5.16.0-rc1+\n[  343.237569] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),\nBIOS 1.11.0-2.el7 04/01/2014\n[  343.238707] RIP: 0010:netem_enqueue+0x1590/0x33c0 [sch_netem]\n[  343.239499] Code: 89 85 58 ff ff ff e8 5f 5d e9 d3 48 8b b5 48 ff ff\nff 8b 8d 50 ff ff ff 8b 85 58 ff ff ff 48 8b bd 70 ff ff ff 31 d2 2b 4f\n74 \u003cf7\u003e f1 48 b8 00 00 00 00 00 fc ff df 49 01 d5 4c 89 e9 48 c1 e9 03\n[  343.241883] RSP: 0018:ffff88800bcd7368 EFLAGS: 00010246\n[  343.242589] RAX: 00000000ba7c0a9c RBX: 0000000000000001 RCX:\n0000000000000000\n[  343.243542] RDX: 0000000000000000 RSI: ffff88800f8edb10 RDI:\nffff88800f8eda40\n[  343.244474] RBP: ffff88800bcd7458 R08: 0000000000000000 R09:\nffffffff94fb8445\n[  343.245403] R10: ffffffff94fb8336 R11: ffffffff94fb8445 R12:\n0000000000000000\n[  343.246355] R13: ffff88800a5a7000 R14: ffff88800a5b5800 R15:\n0000000000000020\n[  343.247291] FS:  00007fdde2bd7700(0000) GS:ffff888109780000(0000)\nknlGS:0000000000000000\n[  343.248350] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[  343.249120] CR2: 00000000200000c0 CR3: 000000000ef4c000 CR4:\n00000000000006e0\n[  343.250076] Call Trace:\n[  343.250423]  \u003cTASK\u003e\n[  343.250713]  ? memcpy+0x4d/0x60\n[  343.251162]  ? netem_init+0xa0/0xa0 [sch_netem]\n[  343.251795]  ? __sanitizer_cov_trace_pc+0x21/0x60\n[  343.252443]  netem_enqueue+0xe28/0x33c0 [sch_netem]\n[  343.253102]  ? stack_trace_save+0x87/0xb0\n[  343.253655]  ? filter_irq_stacks+0xb0/0xb0\n[  343.254220]  ? netem_init+0xa0/0xa0 [sch_netem]\n[  343.254837]  ? __kasan_check_write+0x14/0x20\n[  343.255418]  ? _raw_spin_lock+0x88/0xd6\n[  343.255953]  dev_qdisc_enqueue+0x50/0x180\n[  343.256508]  __dev_queue_xmit+0x1a7e/0x3090\n[  343.257083]  ? netdev_core_pick_tx+0x300/0x300\n[  343.257690]  ? check_kcov_mode+0x10/0x40\n[  343.258219]  ? _raw_spin_unlock_irqrestore+0x29/0x40\n[  343.258899]  ? __kasan_init_slab_obj+0x24/0x30\n[  343.259529]  ? setup_object.isra.71+0x23/0x90\n[  343.260121]  ? new_slab+0x26e/0x4b0\n[  343.260609]  ? kasan_poison+0x3a/0x50\n[  343.261118]  ? kasan_unpoison+0x28/0x50\n[  343.261637]  ? __kasan_slab_alloc+0x71/0x90\n[  343.262214]  ? memcpy+0x4d/0x60\n[  343.262674]  ? write_comp_data+0x2f/0x90\n[  343.263209]  ? __kasan_check_write+0x14/0x20\n[  343.263802]  ? __skb_clone+0x5d6/0x840\n[  343.264329]  ? __sanitizer_cov_trace_pc+0x21/0x60\n[  343.264958]  dev_queue_xmit+0x1c/0x20\n[  343.265470]  netlink_deliver_tap+0x652/0x9c0\n[  343.266067]  netlink_unicast+0x5a0/0x7f0\n[  343.266608]  ? netlink_attachskb+0x860/0x860\n[  343.267183]  ? __sanitizer_cov_trace_pc+0x21/0x60\n[  343.267820]  ? write_comp_data+0x2f/0x90\n[  343.268367]  netlink_sendmsg+0x922/0xe80\n[  343.268899]  ? netlink_unicast+0x7f0/0x7f0\n[  343.269472]  ? __sanitizer_cov_trace_pc+0x21/0x60\n[  343.270099]  ? write_comp_data+0x2f/0x90\n[  343.270644]  ? netlink_unicast+0x7f0/0x7f0\n[  343.271210]  sock_sendmsg+0x155/0x190\n[  343.271721]  ____sys_sendmsg+0x75f/0x8f0\n[  343.272262]  ? kernel_sendmsg+0x60/0x60\n[  343.272788]  ? write_comp_data+0x2f/0x90\n[  343.273332]  ? write_comp_data+0x2f/0x90\n[  343.273869]  ___sys_sendmsg+0x10f/0x190\n[  343.274405]  ? sendmsg_copy_msghdr+0x80/0x80\n[  343.274984]  ? slab_post_alloc_hook+0x70/0x230\n[  343.275597]  ? futex_wait_setup+0x240/0x240\n[  343.276175]  ? security_file_alloc+0x3e/0x170\n[  343.276779]  ? write_comp_d\n---truncated---"
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          "url": "https://git.kernel.org/stable/c/ff3f517bf7138e01a17369042908a3f345c0ee41"
        },
        {
          "url": "https://git.kernel.org/stable/c/c0315e93552e0d840e9edc6abd71c7db82ec8f51"
        },
        {
          "url": "https://git.kernel.org/stable/c/dadce61247c6230489527cc5e343b6002d1114c5"
        },
        {
          "url": "https://git.kernel.org/stable/c/4c986072a8c9249b9398c7a18f216dc26a9f0e35"
        },
        {
          "url": "https://git.kernel.org/stable/c/f123cffdd8fe8ea6c7fded4b88516a42798797d0"
        }
      ],
      "title": "net: netlink: af_netlink: Prevent empty skb by adding a check on len.",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2021-47606",
    "datePublished": "2024-06-19T14:54:05.025Z",
    "dateReserved": "2024-05-24T15:11:00.737Z",
    "dateUpdated": "2026-05-11T13:57:47.811Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
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      "date": "2026-10-01",
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                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "status": "affected",
                    "version": "3.11"
                  },
                  {
                    "lessThan": "3.11",
                    "status": "unaffected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "4.4.*",
                    "status": "unaffected",
                    "version": "4.4.296",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "4.9.*",
                    "status": "unaffected",
                    "version": "4.9.294",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "4.14.*",
                    "status": "unaffected",
                    "version": "4.14.259",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "4.19.*",
                    "status": "unaffected",
                    "version": "4.19.222",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.4.*",
                    "status": "unaffected",
                    "version": "5.4.167",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.10.*",
                    "status": "unaffected",
                    "version": "5.10.87",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.15.*",
                    "status": "unaffected",
                    "version": "5.15.10",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "5.16",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "configurations": [
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                    "vulnerable": true
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                "negate": false,
                "operator": "OR"
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        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: netlink: af_netlink: Prevent empty skb by adding a check on len.\n\nAdding a check on len parameter to avoid empty skb. This prevents a\ndivision error in netem_enqueue function which is caused when skb-\u003elen=0\nand skb-\u003edata_len=0 in the randomized corruption step as shown below.\n\nskb-\u003edata[prandom_u32() % skb_headlen(skb)] ^= 1\u003c\u003c(prandom_u32() % 8);\n\nCrash Report:\n[  343.170349] netdevsim netdevsim0 netdevsim3: set [1, 0] type 2 family\n0 port 6081 - 0\n[  343.216110] netem: version 1.3\n[  343.235841] divide error: 0000 [#1] PREEMPT SMP KASAN NOPTI\n[  343.236680] CPU: 3 PID: 4288 Comm: reproducer Not tainted 5.16.0-rc1+\n[  343.237569] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),\nBIOS 1.11.0-2.el7 04/01/2014\n[  343.238707] RIP: 0010:netem_enqueue+0x1590/0x33c0 [sch_netem]\n[  343.239499] Code: 89 85 58 ff ff ff e8 5f 5d e9 d3 48 8b b5 48 ff ff\nff 8b 8d 50 ff ff ff 8b 85 58 ff ff ff 48 8b bd 70 ff ff ff 31 d2 2b 4f\n74 \u003cf7\u003e f1 48 b8 00 00 00 00 00 fc ff df 49 01 d5 4c 89 e9 48 c1 e9 03\n[  343.241883] RSP: 0018:ffff88800bcd7368 EFLAGS: 00010246\n[  343.242589] RAX: 00000000ba7c0a9c RBX: 0000000000000001 RCX:\n0000000000000000\n[  343.243542] RDX: 0000000000000000 RSI: ffff88800f8edb10 RDI:\nffff88800f8eda40\n[  343.244474] RBP: ffff88800bcd7458 R08: 0000000000000000 R09:\nffffffff94fb8445\n[  343.245403] R10: ffffffff94fb8336 R11: ffffffff94fb8445 R12:\n0000000000000000\n[  343.246355] R13: ffff88800a5a7000 R14: ffff88800a5b5800 R15:\n0000000000000020\n[  343.247291] FS:  00007fdde2bd7700(0000) GS:ffff888109780000(0000)\nknlGS:0000000000000000\n[  343.248350] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[  343.249120] CR2: 00000000200000c0 CR3: 000000000ef4c000 CR4:\n00000000000006e0\n[  343.250076] Call Trace:\n[  343.250423]  \u003cTASK\u003e\n[  343.250713]  ? memcpy+0x4d/0x60\n[  343.251162]  ? netem_init+0xa0/0xa0 [sch_netem]\n[  343.251795]  ? __sanitizer_cov_trace_pc+0x21/0x60\n[  343.252443]  netem_enqueue+0xe28/0x33c0 [sch_netem]\n[  343.253102]  ? stack_trace_save+0x87/0xb0\n[  343.253655]  ? filter_irq_stacks+0xb0/0xb0\n[  343.254220]  ? netem_init+0xa0/0xa0 [sch_netem]\n[  343.254837]  ? __kasan_check_write+0x14/0x20\n[  343.255418]  ? _raw_spin_lock+0x88/0xd6\n[  343.255953]  dev_qdisc_enqueue+0x50/0x180\n[  343.256508]  __dev_queue_xmit+0x1a7e/0x3090\n[  343.257083]  ? netdev_core_pick_tx+0x300/0x300\n[  343.257690]  ? check_kcov_mode+0x10/0x40\n[  343.258219]  ? _raw_spin_unlock_irqrestore+0x29/0x40\n[  343.258899]  ? __kasan_init_slab_obj+0x24/0x30\n[  343.259529]  ? setup_object.isra.71+0x23/0x90\n[  343.260121]  ? new_slab+0x26e/0x4b0\n[  343.260609]  ? kasan_poison+0x3a/0x50\n[  343.261118]  ? kasan_unpoison+0x28/0x50\n[  343.261637]  ? __kasan_slab_alloc+0x71/0x90\n[  343.262214]  ? memcpy+0x4d/0x60\n[  343.262674]  ? write_comp_data+0x2f/0x90\n[  343.263209]  ? __kasan_check_write+0x14/0x20\n[  343.263802]  ? __skb_clone+0x5d6/0x840\n[  343.264329]  ? __sanitizer_cov_trace_pc+0x21/0x60\n[  343.264958]  dev_queue_xmit+0x1c/0x20\n[  343.265470]  netlink_deliver_tap+0x652/0x9c0\n[  343.266067]  netlink_unicast+0x5a0/0x7f0\n[  343.266608]  ? netlink_attachskb+0x860/0x860\n[  343.267183]  ? __sanitizer_cov_trace_pc+0x21/0x60\n[  343.267820]  ? write_comp_data+0x2f/0x90\n[  343.268367]  netlink_sendmsg+0x922/0xe80\n[  343.268899]  ? netlink_unicast+0x7f0/0x7f0\n[  343.269472]  ? __sanitizer_cov_trace_pc+0x21/0x60\n[  343.270099]  ? write_comp_data+0x2f/0x90\n[  343.270644]  ? netlink_unicast+0x7f0/0x7f0\n[  343.271210]  sock_sendmsg+0x155/0x190\n[  343.271721]  ____sys_sendmsg+0x75f/0x8f0\n[  343.272262]  ? kernel_sendmsg+0x60/0x60\n[  343.272788]  ? write_comp_data+0x2f/0x90\n[  343.273332]  ? write_comp_data+0x2f/0x90\n[  343.273869]  ___sys_sendmsg+0x10f/0x190\n[  343.274405]  ? sendmsg_copy_msghdr+0x80/0x80\n[  343.274984]  ? slab_post_alloc_hook+0x70/0x230\n[  343.275597]  ? futex_wait_setup+0x240/0x240\n[  343.276175]  ? security_file_alloc+0x3e/0x170\n[  343.276779]  ? write_comp_d\n---truncated---"
          },
          {
            "lang": "es",
            "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: net: netlink: af_netlink: Evite el skb vac\u00edo agregando una marca en len. Agregar una verificaci\u00f3n en el par\u00e1metro len para evitar skb vac\u00edo. Esto evita un error de divisi\u00f3n en la funci\u00f3n netem_enqueue que se produce cuando skb-\u0026gt;len=0 y skb-\u0026gt;data_len=0 en el paso de corrupci\u00f3n aleatoria como se muestra a continuaci\u00f3n. skb-\u0026gt;datos[prandom_u32() % skb_headlen(skb)] ^= 1\u0026lt;\u0026lt;(prandom_u32() % 8); Informe de fallo: [343.170349] netdevsim netdevsim0 netdevsim3: establecer [1, 0] tipo 2 familia 0 puerto 6081 - 0 [343.216110] netem: versi\u00f3n 1.3 [343.235841] error de divisi\u00f3n: 0000 [#1] PREEMPT SMP KASAN NOPTI [ 80] CPU : 3 PID: 4288 Comm: reproductor No contaminado 5.16.0-rc1+ [ 343.237569] Nombre del hardware: PC est\u00e1ndar QEMU (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 01/04/2014 [ 343.238707] RIP: 0010:netem_enqueue+0x1590/0x33c0 [sch_netem] [ 343.239499] C\u00f3digo: 89 85 58 ff ff ff e8 5f 5d e9 d3 48 8b b5 48 ff ff ff 8b 8d 50 ff ff 8b 85 58 ff ff 4 8 8b bd 70 y sigs. ff ff 31 d2 2b 4f 74  f1 48 b8 00 00 00 00 00 fc ff df 49 01 d5 4c 89 e9 48 c1 e9 03 [ 343.241883] RSP: 0018:ffff88800bcd7368 EFLAGS: 46 [343.242589] RAX: 00000000ba7c0a9c RBX: 0000000000000001 RCX: 0000000000000000 [ 343.243542] RDX: 0000000000000000 RSI: ffff88800f8edb10 RDI: ffff88800f8eda40 [ 343.244474] RBP: ff88800bcd7458 R08: 0000000000000000 R09: ffffffff94fb8445 [ 343.245403] R10: ffffffff94fb8336 R11: ffffffff94fb8445 R12: 0000000000000000 [ 343. 246355] R13: ffff88800a5a7000 R14: ffff88800a5b5800 R15 : 0000000000000020 [ 343.247291] FS: 00007fdde2bd7700(0000) GS:ffff888109780000(0000) knlGS:0000000000000000 [ 343.248350] CS: 0010 DS: 000 ES: 0000 CR0: 0000000080050033 [ 343.249120] CR2: 00000000200000c0 CR3: 000000000ef4c000 CR4: 00000000000006e0 [ 343.250076] Seguimiento de llamadas: [ 343.250423]  [ 343.250713] ? memcpy+0x4d/0x60 [343.251162]? netem_init+0xa0/0xa0 [sch_netem] [ 343.251795] ? __sanitizer_cov_trace_pc+0x21/0x60 [ 343.252443] netem_enqueue+0xe28/0x33c0 [sch_netem] [ 343.253102] ? stack_trace_save+0x87/0xb0 [343.253655]? filter_irq_stacks+0xb0/0xb0 [343.254220]? netem_init+0xa0/0xa0 [sch_netem] [ 343.254837] ? __kasan_check_write+0x14/0x20 [343.255418]? _raw_spin_lock+0x88/0xd6 [ 343.255953] dev_qdisc_enqueue+0x50/0x180 [ 343.256508] __dev_queue_xmit+0x1a7e/0x3090 [ 343.257083] ? netdev_core_pick_tx+0x300/0x300 [343.257690]? check_kcov_mode+0x10/0x40 [343.258219]? _raw_spin_unlock_irqrestore+0x29/0x40 [343.258899]? __kasan_init_slab_obj+0x24/0x30 [343.259529] ? setup_object.isra.71+0x23/0x90 [343.260121]? nueva_losa+0x26e/0x4b0 [ 343.260609] ? kasan_poison+0x3a/0x50 [ 343.261118] ? kasan_unpoison+0x28/0x50 [343.261637]? __kasan_slab_alloc+0x71/0x90 [343.262214]? memcpy+0x4d/0x60 [343.262674]? write_comp_data+0x2f/0x90 [343.263209]? __kasan_check_write+0x14/0x20 [343.263802]? __skb_clone+0x5d6/0x840 [343.264329]? __sanitizer_cov_trace_pc+0x21/0x60 [ 343.264958] dev_queue_xmit+0x1c/0x20 [ 343.265470] netlink_deliver_tap+0x652/0x9c0 [ 343.266067] netlink_unicast+0x5a0/0x7f0 [ 343. 266608] ? netlink_attachskb+0x860/0x860 [343.267183]? __sanitizer_cov_trace_pc+0x21/0x60 [ 343.267820] ? write_comp_data+0x2f/0x90 [343.268367] netlink_sendmsg+0x922/0xe80 [343.268899]? netlink_unicast+0x7f0/0x7f0 [343.269472]? __sanitizer_cov_trace_pc+0x21/0x60 [343.270099] ? write_comp_data+0x2f/0x90 [343.270644]? netlink_unicast+0x7f0/0x7f0 [343.271210] sock_sendmsg+0x155/0x190 [343.271721] ____sys_sendmsg+0x75f/0x8f0 [343.272262] ? kernel_sendmsg+0x60/0x60 [343.272788]? write_comp_data+0x2f/0x90 [343.273332]? write_comp_data+0x2f/0x90 [ 343.273869] ___sys_sendmsg+0x10f/0x190 [ 343.274405] ? sendmsg_copy_msghdr+0x80/0x80 [343.274984]? slab_post_alloc_hook+0x70/0x230 [343.275597]? futex_wait_setup+0x240/0x240 [343.276175]? security_file_alloc+0x3e/0x170 [343.276779]? write_comp_d ---truncado---"
          }
        ],
        "id": "CVE-2021-47606",
        "lastModified": "2026-06-17T04:18:08.980",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "LOCAL",
                "availabilityImpact": "HIGH",
                "baseScore": 5.5,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 1.8,
              "impactScore": 3.6,
              "source": "nvd@nist.gov",
              "type": "Primary"
            }
          ],
          "ssvcV203": [
            {
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "ssvcData": {
                "id": "CVE-2021-47606",
                "options": [
                  {
                    "exploitation": "none"
                  },
                  {
                    "automatable": "no"
                  },
                  {
                    "technicalImpact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2024-09-10T17:12:08.038077Z",
                "version": "2.0.3"
              }
            }
          ]
        },
        "published": "2024-06-19T15:15:55.153",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/40cf2e058832d9cfaae98dfd77334926275598b6"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/4c986072a8c9249b9398c7a18f216dc26a9f0e35"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/54e785f7d5c197bc06dbb8053700df7e2a093ced"
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                  "status": "unaffected",
                  "version": "4.4.296",
                  "versionType": "semver"
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                {
                  "lessThanOrEqual": "4.9.*",
                  "status": "unaffected",
                  "version": "4.9.294",
                  "versionType": "semver"
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                {
                  "lessThanOrEqual": "4.14.*",
                  "status": "unaffected",
                  "version": "4.14.259",
                  "versionType": "semver"
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                  "version": "4.19.222",
                  "versionType": "semver"
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                  "version": "5.4.167",
                  "versionType": "semver"
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                  "version": "5.10.87",
                  "versionType": "semver"
                },
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                  "version": "5.15.10",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "*",
                  "status": "unaffected",
                  "version": "5.16",
                  "versionType": "original_commit_for_fix"
                }
              ]
            }
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          "cpeApplicability": [
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                      "vulnerable": true
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                    {
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                    {
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          "descriptions": [
            {
              "lang": "en",
              "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: netlink: af_netlink: Prevent empty skb by adding a check on len.\n\nAdding a check on len parameter to avoid empty skb. This prevents a\ndivision error in netem_enqueue function which is caused when skb-\u003elen=0\nand skb-\u003edata_len=0 in the randomized corruption step as shown below.\n\nskb-\u003edata[prandom_u32() % skb_headlen(skb)] ^= 1\u003c\u003c(prandom_u32() % 8);\n\nCrash Report:\n[  343.170349] netdevsim netdevsim0 netdevsim3: set [1, 0] type 2 family\n0 port 6081 - 0\n[  343.216110] netem: version 1.3\n[  343.235841] divide error: 0000 [#1] PREEMPT SMP KASAN NOPTI\n[  343.236680] CPU: 3 PID: 4288 Comm: reproducer Not tainted 5.16.0-rc1+\n[  343.237569] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),\nBIOS 1.11.0-2.el7 04/01/2014\n[  343.238707] RIP: 0010:netem_enqueue+0x1590/0x33c0 [sch_netem]\n[  343.239499] Code: 89 85 58 ff ff ff e8 5f 5d e9 d3 48 8b b5 48 ff ff\nff 8b 8d 50 ff ff ff 8b 85 58 ff ff ff 48 8b bd 70 ff ff ff 31 d2 2b 4f\n74 \u003cf7\u003e f1 48 b8 00 00 00 00 00 fc ff df 49 01 d5 4c 89 e9 48 c1 e9 03\n[  343.241883] RSP: 0018:ffff88800bcd7368 EFLAGS: 00010246\n[  343.242589] RAX: 00000000ba7c0a9c RBX: 0000000000000001 RCX:\n0000000000000000\n[  343.243542] RDX: 0000000000000000 RSI: ffff88800f8edb10 RDI:\nffff88800f8eda40\n[  343.244474] RBP: ffff88800bcd7458 R08: 0000000000000000 R09:\nffffffff94fb8445\n[  343.245403] R10: ffffffff94fb8336 R11: ffffffff94fb8445 R12:\n0000000000000000\n[  343.246355] R13: ffff88800a5a7000 R14: ffff88800a5b5800 R15:\n0000000000000020\n[  343.247291] FS:  00007fdde2bd7700(0000) GS:ffff888109780000(0000)\nknlGS:0000000000000000\n[  343.248350] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[  343.249120] CR2: 00000000200000c0 CR3: 000000000ef4c000 CR4:\n00000000000006e0\n[  343.250076] Call Trace:\n[  343.250423]  \u003cTASK\u003e\n[  343.250713]  ? memcpy+0x4d/0x60\n[  343.251162]  ? netem_init+0xa0/0xa0 [sch_netem]\n[  343.251795]  ? __sanitizer_cov_trace_pc+0x21/0x60\n[  343.252443]  netem_enqueue+0xe28/0x33c0 [sch_netem]\n[  343.253102]  ? stack_trace_save+0x87/0xb0\n[  343.253655]  ? filter_irq_stacks+0xb0/0xb0\n[  343.254220]  ? netem_init+0xa0/0xa0 [sch_netem]\n[  343.254837]  ? __kasan_check_write+0x14/0x20\n[  343.255418]  ? _raw_spin_lock+0x88/0xd6\n[  343.255953]  dev_qdisc_enqueue+0x50/0x180\n[  343.256508]  __dev_queue_xmit+0x1a7e/0x3090\n[  343.257083]  ? netdev_core_pick_tx+0x300/0x300\n[  343.257690]  ? check_kcov_mode+0x10/0x40\n[  343.258219]  ? _raw_spin_unlock_irqrestore+0x29/0x40\n[  343.258899]  ? __kasan_init_slab_obj+0x24/0x30\n[  343.259529]  ? setup_object.isra.71+0x23/0x90\n[  343.260121]  ? new_slab+0x26e/0x4b0\n[  343.260609]  ? kasan_poison+0x3a/0x50\n[  343.261118]  ? kasan_unpoison+0x28/0x50\n[  343.261637]  ? __kasan_slab_alloc+0x71/0x90\n[  343.262214]  ? memcpy+0x4d/0x60\n[  343.262674]  ? write_comp_data+0x2f/0x90\n[  343.263209]  ? __kasan_check_write+0x14/0x20\n[  343.263802]  ? __skb_clone+0x5d6/0x840\n[  343.264329]  ? __sanitizer_cov_trace_pc+0x21/0x60\n[  343.264958]  dev_queue_xmit+0x1c/0x20\n[  343.265470]  netlink_deliver_tap+0x652/0x9c0\n[  343.266067]  netlink_unicast+0x5a0/0x7f0\n[  343.266608]  ? netlink_attachskb+0x860/0x860\n[  343.267183]  ? __sanitizer_cov_trace_pc+0x21/0x60\n[  343.267820]  ? write_comp_data+0x2f/0x90\n[  343.268367]  netlink_sendmsg+0x922/0xe80\n[  343.268899]  ? netlink_unicast+0x7f0/0x7f0\n[  343.269472]  ? __sanitizer_cov_trace_pc+0x21/0x60\n[  343.270099]  ? write_comp_data+0x2f/0x90\n[  343.270644]  ? netlink_unicast+0x7f0/0x7f0\n[  343.271210]  sock_sendmsg+0x155/0x190\n[  343.271721]  ____sys_sendmsg+0x75f/0x8f0\n[  343.272262]  ? kernel_sendmsg+0x60/0x60\n[  343.272788]  ? write_comp_data+0x2f/0x90\n[  343.273332]  ? write_comp_data+0x2f/0x90\n[  343.273869]  ___sys_sendmsg+0x10f/0x190\n[  343.274405]  ? sendmsg_copy_msghdr+0x80/0x80\n[  343.274984]  ? slab_post_alloc_hook+0x70/0x230\n[  343.275597]  ? futex_wait_setup+0x240/0x240\n[  343.276175]  ? security_file_alloc+0x3e/0x170\n[  343.276779]  ? write_comp_d\n---truncated---"
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2025-12-10T07:12:42.639Z",
            "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "shortName": "Linux"
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          "references": [
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            {
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            },
            {
              "url": "https://git.kernel.org/stable/c/54e785f7d5c197bc06dbb8053700df7e2a093ced"
            },
            {
              "url": "https://git.kernel.org/stable/c/ff3f517bf7138e01a17369042908a3f345c0ee41"
            },
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              "url": "https://git.kernel.org/stable/c/c0315e93552e0d840e9edc6abd71c7db82ec8f51"
            },
            {
              "url": "https://git.kernel.org/stable/c/dadce61247c6230489527cc5e343b6002d1114c5"
            },
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              "url": "https://git.kernel.org/stable/c/4c986072a8c9249b9398c7a18f216dc26a9f0e35"
            },
            {
              "url": "https://git.kernel.org/stable/c/f123cffdd8fe8ea6c7fded4b88516a42798797d0"
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          ],
          "title": "net: netlink: af_netlink: Prevent empty skb by adding a check on len.",
          "x_generator": {
            "engine": "bippy-1.2.0"
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      },
      "cveMetadata": {
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "assignerShortName": "Linux",
        "cveId": "CVE-2021-47606",
        "datePublished": "2024-06-19T14:54:05.025Z",
        "dateReserved": "2024-05-24T15:11:00.737Z",
        "dateUpdated": "2025-12-10T07:12:42.639Z",
        "state": "PUBLISHED"
      },
      "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

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.



Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.