CVE-2026-43496 (GCVE-0-2026-43496)

Vulnerability from cvelistv5 – Published: 2026-05-21 12:12 – Updated: 2026-06-14 17:45
VLAI
Title
net/sched: sch_red: Replace direct dequeue call with peek and qdisc_dequeue_peeked
Summary
In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_red: Replace direct dequeue call with peek and qdisc_dequeue_peeked When red qdisc has children (eg qfq qdisc) whose peek() callback is qdisc_peek_dequeued(), we could get a kernel panic. When the parent of such qdiscs (eg illustrated in patch #3 as tbf) wants to retrieve an skb from its child (red in this case), it will do the following: 1a. do a peek() - and when sensing there's an skb the child can offer, then - the child in this case(red) calls its child's (qfq) peek. qfq does the right thing and will return the gso_skb queue packet. Note: if there wasnt a gso_skb entry then qfq will store it there. 1b. invoke a dequeue() on the child (red). And herein lies the problem. - red will call the child's dequeue() which will essentially just try to grab something of qfq's queue. [ 78.667668][ T363] KASAN: null-ptr-deref in range [0x0000000000000048-0x000000000000004f] [ 78.667927][ T363] CPU: 1 UID: 0 PID: 363 Comm: ping Not tainted 7.1.0-rc1-00033-g46f74a3f7d57-dirty #790 PREEMPT(full) [ 78.668263][ T363] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 78.668486][ T363] RIP: 0010:qfq_dequeue+0x446/0xc90 [sch_qfq] [ 78.668718][ T363] Code: 54 c0 e8 dd 90 00 f1 48 c7 c7 e0 03 54 c0 48 89 de e8 ce 90 00 f1 48 8d 7b 48 b8 ff ff 37 00 48 89 fa 48 c1 e0 2a 48 c1 ea 03 <80> 3c 02 00 74 05 e8 ef a1 e1 f1 48 8b 7b 48 48 8d 54 24 58 48 8d [ 78.669312][ T363] RSP: 0018:ffff88810de573e0 EFLAGS: 00010216 [ 78.669533][ T363] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 78.669790][ T363] RDX: 0000000000000009 RSI: 0000000000000004 RDI: 0000000000000048 [ 78.670044][ T363] RBP: ffff888110dc4000 R08: ffffffffb1b0885a R09: fffffbfff6ba9078 [ 78.670297][ T363] R10: 0000000000000003 R11: ffff888110e31c80 R12: 0000001880000000 [ 78.670560][ T363] R13: ffff888110dc4150 R14: ffff888110dc42b8 R15: 0000000000000200 [ 78.670814][ T363] FS: 00007f66a8f09c40(0000) GS:ffff888163428000(0000) knlGS:0000000000000000 [ 78.671110][ T363] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 78.671324][ T363] CR2: 000055db4c6a30a8 CR3: 000000010da67000 CR4: 0000000000750ef0 [ 78.671585][ T363] PKRU: 55555554 [ 78.671713][ T363] Call Trace: [ 78.671843][ T363] <TASK> [ 78.671936][ T363] ? __pfx_qfq_dequeue+0x10/0x10 [sch_qfq] [ 78.672148][ T363] ? __pfx__printk+0x10/0x10 [ 78.672322][ T363] ? srso_alias_return_thunk+0x5/0xfbef5 [ 78.672496][ T363] ? lockdep_hardirqs_on_prepare+0xa8/0x1a0 [ 78.672706][ T363] ? srso_alias_return_thunk+0x5/0xfbef5 [ 78.672875][ T363] ? trace_hardirqs_on+0x19/0x1a0 [ 78.673047][ T363] red_dequeue+0x65/0x270 [sch_red] [ 78.673217][ T363] ? srso_alias_return_thunk+0x5/0xfbef5 [ 78.673385][ T363] tbf_dequeue.cold+0xb0/0x70c [sch_tbf] [ 78.673566][ T363] __qdisc_run+0x169/0x1900 The right thing to do in #1b is to grab the skb off gso_skb queue. This patchset fixes that issue by changing #1b to use qdisc_dequeue_peeked() method instead.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 77be155cba4e163e8bba9fd27222a8b6189ec4f7 , < 03b0aaeba082ae981a0dfe96cdd03d02050537a1 (git)
Affected: 77be155cba4e163e8bba9fd27222a8b6189ec4f7 , < c7335f4dc0fa21f7015b910c6fc2f4d599732328 (git)
Affected: 77be155cba4e163e8bba9fd27222a8b6189ec4f7 , < 45cd83c5c470ba49fe261489c8358ad7b9df7c45 (git)
Affected: 77be155cba4e163e8bba9fd27222a8b6189ec4f7 , < 36aa34f42cb6842cf371f3a2d3e855d24fd57a50 (git)
Affected: 77be155cba4e163e8bba9fd27222a8b6189ec4f7 , < ce051eede433f876d322ac3550a36a3c6fc4c231 (git)
Affected: 77be155cba4e163e8bba9fd27222a8b6189ec4f7 , < 8d09618840b99ef00154d3e731ce9b11e096196d (git)
Affected: 77be155cba4e163e8bba9fd27222a8b6189ec4f7 , < 587dcf970a525f543d8b5855d9f37a4ca97b76ef (git)
Affected: 77be155cba4e163e8bba9fd27222a8b6189ec4f7 , < 458d5615272d3de535748342eb68ca492343048c (git)
guessed Create a notification for this product.
Linux Linux Affected: 2.6.29
Unaffected: 0 , < 2.6.29 (semver)
Unaffected: 5.10.258 , ≤ 5.10.* (semver)
Unaffected: 5.15.209 , ≤ 5.15.* (semver)
Unaffected: 6.1.175 , ≤ 6.1.* (semver)
Unaffected: 6.6.140 , ≤ 6.6.* (semver)
Unaffected: 6.12.88 , ≤ 6.12.* (semver)
Unaffected: 6.18.30 , ≤ 6.18.* (semver)
Unaffected: 7.0.7 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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{
  "containers": {
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          "product": "Linux",
          "programFiles": [
            "net/sched/sch_red.c"
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            },
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              "status": "unaffected",
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              "versionType": "semver"
            },
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              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.209",
              "versionType": "semver"
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              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
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              "status": "unaffected",
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              "versionType": "semver"
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            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.88",
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              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.30",
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            {
              "lessThanOrEqual": "7.0.*",
              "status": "unaffected",
              "version": "7.0.7",
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              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
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                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.258",
                  "versionStartIncluding": "2.6.29",
                  "vulnerable": true
                },
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                  "vulnerable": true
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                  "vulnerable": true
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                {
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                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                  "versionStartIncluding": "2.6.29",
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                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sch_red: Replace direct dequeue call with peek and qdisc_dequeue_peeked\n\nWhen red qdisc has children (eg qfq qdisc) whose peek() callback is\nqdisc_peek_dequeued(), we could get a kernel panic. When the parent of such\nqdiscs (eg illustrated in patch #3 as tbf) wants to retrieve an skb from\nits child (red in this case), it will do the following:\n 1a. do a peek() - and when sensing there\u0027s an skb the child can offer, then\n     - the child in this case(red) calls its child\u0027s (qfq) peek.\n        qfq does the right thing and will return the gso_skb queue packet.\n        Note: if there wasnt a gso_skb entry then qfq will store it there.\n 1b. invoke a dequeue() on the child (red). And herein lies the problem.\n     - red will call the child\u0027s dequeue() which will essentially just\n       try to grab something of qfq\u0027s queue.\n\n[   78.667668][  T363] KASAN: null-ptr-deref in range [0x0000000000000048-0x000000000000004f]\n[   78.667927][  T363] CPU: 1 UID: 0 PID: 363 Comm: ping Not tainted 7.1.0-rc1-00033-g46f74a3f7d57-dirty #790 PREEMPT(full)\n[   78.668263][  T363] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011\n[   78.668486][  T363] RIP: 0010:qfq_dequeue+0x446/0xc90 [sch_qfq]\n[   78.668718][  T363] Code: 54 c0 e8 dd 90 00 f1 48 c7 c7 e0 03 54 c0 48 89 de e8 ce 90 00 f1 48 8d 7b 48 b8 ff ff 37 00 48 89 fa 48 c1 e0 2a 48 c1 ea 03 \u003c80\u003e 3c 02 00 74 05 e8 ef a1 e1 f1 48 8b 7b 48 48 8d 54 24 58 48 8d\n[   78.669312][  T363] RSP: 0018:ffff88810de573e0 EFLAGS: 00010216\n[   78.669533][  T363] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000\n[   78.669790][  T363] RDX: 0000000000000009 RSI: 0000000000000004 RDI: 0000000000000048\n[   78.670044][  T363] RBP: ffff888110dc4000 R08: ffffffffb1b0885a R09: fffffbfff6ba9078\n[   78.670297][  T363] R10: 0000000000000003 R11: ffff888110e31c80 R12: 0000001880000000\n[   78.670560][  T363] R13: ffff888110dc4150 R14: ffff888110dc42b8 R15: 0000000000000200\n[   78.670814][  T363] FS:  00007f66a8f09c40(0000) GS:ffff888163428000(0000) knlGS:0000000000000000\n[   78.671110][  T363] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[   78.671324][  T363] CR2: 000055db4c6a30a8 CR3: 000000010da67000 CR4: 0000000000750ef0\n[   78.671585][  T363] PKRU: 55555554\n[   78.671713][  T363] Call Trace:\n[   78.671843][  T363]  \u003cTASK\u003e\n[   78.671936][  T363]  ? __pfx_qfq_dequeue+0x10/0x10 [sch_qfq]\n[   78.672148][  T363]  ? __pfx__printk+0x10/0x10\n[   78.672322][  T363]  ? srso_alias_return_thunk+0x5/0xfbef5\n[   78.672496][  T363]  ? lockdep_hardirqs_on_prepare+0xa8/0x1a0\n[   78.672706][  T363]  ? srso_alias_return_thunk+0x5/0xfbef5\n[   78.672875][  T363]  ? trace_hardirqs_on+0x19/0x1a0\n[   78.673047][  T363]  red_dequeue+0x65/0x270 [sch_red]\n[   78.673217][  T363]  ? srso_alias_return_thunk+0x5/0xfbef5\n[   78.673385][  T363]  tbf_dequeue.cold+0xb0/0x70c [sch_tbf]\n[   78.673566][  T363]  __qdisc_run+0x169/0x1900\n\nThe right thing to do in #1b is to grab the skb off gso_skb queue.\nThis patchset fixes that issue by changing #1b to use qdisc_dequeue_peeked()\nmethod instead."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-06-14T17:45:26.779Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/03b0aaeba082ae981a0dfe96cdd03d02050537a1"
        },
        {
          "url": "https://git.kernel.org/stable/c/c7335f4dc0fa21f7015b910c6fc2f4d599732328"
        },
        {
          "url": "https://git.kernel.org/stable/c/45cd83c5c470ba49fe261489c8358ad7b9df7c45"
        },
        {
          "url": "https://git.kernel.org/stable/c/36aa34f42cb6842cf371f3a2d3e855d24fd57a50"
        },
        {
          "url": "https://git.kernel.org/stable/c/ce051eede433f876d322ac3550a36a3c6fc4c231"
        },
        {
          "url": "https://git.kernel.org/stable/c/8d09618840b99ef00154d3e731ce9b11e096196d"
        },
        {
          "url": "https://git.kernel.org/stable/c/587dcf970a525f543d8b5855d9f37a4ca97b76ef"
        },
        {
          "url": "https://git.kernel.org/stable/c/458d5615272d3de535748342eb68ca492343048c"
        }
      ],
      "title": "net/sched: sch_red: Replace direct dequeue call with peek and qdisc_dequeue_peeked",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-43496",
    "datePublished": "2026-05-21T12:12:46.584Z",
    "dateReserved": "2026-05-01T14:12:56.013Z",
    "dateUpdated": "2026-06-14T17:45:26.779Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-43496",
      "date": "2026-09-21",
      "epss": "0.00118",
      "percentile": "0.01977"
    },
    "microsoft_vex": {
      "current_release_date": "2026-06-09T14:40:40.000Z",
      "cve": "CVE-2026-43496",
      "id": "msrc_CVE-2026-43496",
      "initial_release_date": "2026-05-02T00:00:00.000Z",
      "product_status:fixed": "1",
      "product_status:known_affected": "1",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "net/sched: sch_red: Replace direct dequeue call with peek and qdisc_dequeue_peeked",
      "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-43496.json",
      "version": "2"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
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                ],
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                  {
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                    "versionType": "git"
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                    "versionType": "git"
                  }
                ]
              },
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                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
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                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
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                    "version": "5.10.258",
                    "versionType": "semver"
                  },
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                    "status": "unaffected",
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                    "versionType": "semver"
                  },
                  {
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                    "status": "unaffected",
                    "version": "6.1.175",
                    "versionType": "semver"
                  },
                  {
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                    "status": "unaffected",
                    "version": "6.6.140",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.12.*",
                    "status": "unaffected",
                    "version": "6.12.88",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.18.*",
                    "status": "unaffected",
                    "version": "6.18.30",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "7.0.*",
                    "status": "unaffected",
                    "version": "7.0.7",
                    "versionType": "semver"
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                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "7.1",
                    "versionType": "original_commit_for_fix"
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        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sch_red: Replace direct dequeue call with peek and qdisc_dequeue_peeked\n\nWhen red qdisc has children (eg qfq qdisc) whose peek() callback is\nqdisc_peek_dequeued(), we could get a kernel panic. When the parent of such\nqdiscs (eg illustrated in patch #3 as tbf) wants to retrieve an skb from\nits child (red in this case), it will do the following:\n 1a. do a peek() - and when sensing there\u0027s an skb the child can offer, then\n     - the child in this case(red) calls its child\u0027s (qfq) peek.\n        qfq does the right thing and will return the gso_skb queue packet.\n        Note: if there wasnt a gso_skb entry then qfq will store it there.\n 1b. invoke a dequeue() on the child (red). And herein lies the problem.\n     - red will call the child\u0027s dequeue() which will essentially just\n       try to grab something of qfq\u0027s queue.\n\n[   78.667668][  T363] KASAN: null-ptr-deref in range [0x0000000000000048-0x000000000000004f]\n[   78.667927][  T363] CPU: 1 UID: 0 PID: 363 Comm: ping Not tainted 7.1.0-rc1-00033-g46f74a3f7d57-dirty #790 PREEMPT(full)\n[   78.668263][  T363] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011\n[   78.668486][  T363] RIP: 0010:qfq_dequeue+0x446/0xc90 [sch_qfq]\n[   78.668718][  T363] Code: 54 c0 e8 dd 90 00 f1 48 c7 c7 e0 03 54 c0 48 89 de e8 ce 90 00 f1 48 8d 7b 48 b8 ff ff 37 00 48 89 fa 48 c1 e0 2a 48 c1 ea 03 \u003c80\u003e 3c 02 00 74 05 e8 ef a1 e1 f1 48 8b 7b 48 48 8d 54 24 58 48 8d\n[   78.669312][  T363] RSP: 0018:ffff88810de573e0 EFLAGS: 00010216\n[   78.669533][  T363] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000\n[   78.669790][  T363] RDX: 0000000000000009 RSI: 0000000000000004 RDI: 0000000000000048\n[   78.670044][  T363] RBP: ffff888110dc4000 R08: ffffffffb1b0885a R09: fffffbfff6ba9078\n[   78.670297][  T363] R10: 0000000000000003 R11: ffff888110e31c80 R12: 0000001880000000\n[   78.670560][  T363] R13: ffff888110dc4150 R14: ffff888110dc42b8 R15: 0000000000000200\n[   78.670814][  T363] FS:  00007f66a8f09c40(0000) GS:ffff888163428000(0000) knlGS:0000000000000000\n[   78.671110][  T363] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[   78.671324][  T363] CR2: 000055db4c6a30a8 CR3: 000000010da67000 CR4: 0000000000750ef0\n[   78.671585][  T363] PKRU: 55555554\n[   78.671713][  T363] Call Trace:\n[   78.671843][  T363]  \u003cTASK\u003e\n[   78.671936][  T363]  ? __pfx_qfq_dequeue+0x10/0x10 [sch_qfq]\n[   78.672148][  T363]  ? __pfx__printk+0x10/0x10\n[   78.672322][  T363]  ? srso_alias_return_thunk+0x5/0xfbef5\n[   78.672496][  T363]  ? lockdep_hardirqs_on_prepare+0xa8/0x1a0\n[   78.672706][  T363]  ? srso_alias_return_thunk+0x5/0xfbef5\n[   78.672875][  T363]  ? trace_hardirqs_on+0x19/0x1a0\n[   78.673047][  T363]  red_dequeue+0x65/0x270 [sch_red]\n[   78.673217][  T363]  ? srso_alias_return_thunk+0x5/0xfbef5\n[   78.673385][  T363]  tbf_dequeue.cold+0xb0/0x70c [sch_tbf]\n[   78.673566][  T363]  __qdisc_run+0x169/0x1900\n\nThe right thing to do in #1b is to grab the skb off gso_skb queue.\nThis patchset fixes that issue by changing #1b to use qdisc_dequeue_peeked()\nmethod instead."
          },
          {
            "lang": "es",
            "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nnet/sched: sch_red: Reemplazar la llamada directa a dequeue con peek y qdisc_dequeue_peeked\n\nCuando red qdisc tiene hijos (por ejemplo, qfq qdisc) cuya funci\u00f3n de devoluci\u00f3n de llamada peek() es qdisc_peek_dequeued(), podr\u00edamos obtener un p\u00e1nico del kernel. Cuando el padre de tales qdiscs (por ejemplo, ilustrado en el parche #3 como tbf) quiere recuperar un skb de su hijo (red en este caso), har\u00e1 lo siguiente:\n 1a. hacer un peek() - y al detectar que hay un skb que el hijo puede ofrecer, entonces\n     - el hijo en este caso (red) llama al peek de su hijo (qfq).\n        qfq hace lo correcto y devolver\u00e1 el paquete de la cola gso_skb.\n        Nota: si no hubiera una entrada gso_skb, entonces qfq lo almacenar\u00e1 all\u00ed.\n 1b. invocar un dequeue() en el hijo (red). Y aqu\u00ed radica el problema.\n     - red llamar\u00e1 al dequeue() del hijo, que esencialmente solo intentar\u00e1 tomar algo de la cola de qfq.\n\n[   78.667668][  T363] KASAN: null-ptr-deref in range [0x0000000000000048-0x000000000000004f]\n[   78.667927][  T363] CPU: 1 UID: 0 PID: 363 Comm: ping Not tainted 7.1.0-rc1-00033-g46f74a3f7d57-dirty #790 PREEMPT(full)\n[   78.668263][  T363] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011\n[   78.668486][  T363] RIP: 0010:qfq_dequeue+0x446/0xc90 [sch_qfq]\n[   78.668718][  T363] Code: 54 c0 e8 dd 90 00 f1 48 c7 c7 e0 03 54 c0 48 89 de e8 ce 90 00 f1 48 8d 7b 48 b8 ff ff 37 00 48 89 fa 48 c1 e0 2a 48 c1 ea 03 \u003c80\u003e 3c 02 00 74 05 e8 ef a1 e1 f1 48 8b 7b 48 48 8d 54 24 58 48 8d\n[   78.669312][  T363] RSP: 0018:ffff88810de573e0 EFLAGS: 00010216\n[   78.669533][  T363] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000\n[   78.669790][  T363] RDX: 0000000000000009 RSI: 0000000000000004 RDI: 0000000000000048\n[   78.670044][  T363] RBP: ffff888110dc4000 R08: ffffffffb1b0885a R09: fffffbfff6ba9078\n[   78.670297][  T363] R10: 0000000000000003 R11: ffff888110e31c80 R12: 0000001880000000\n[   78.670560][  T363] R13: ffff888110dc4150 R14: ffff888110dc42b8 R15: 0000000000000200\n[   78.670814][  T363] FS:  00007f66a8f09c40(0000) GS:ffff888163428000(0000) knlGS:0000000000000000\n[   78.671110][  T363] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[   78.671324][  T363] CR2: 000055db4c6a30a8 CR3: 000000010da67000 CR4: 0000000000750ef0\n[   78.671585][  T363] PKRU: 55555554\n[   78.671713][  T363] Call Trace:\n[   78.671843][  T363]  \u003cTASK\u003e\n[   78.671936][  T363]  ? __pfx_qfq_dequeue+0x10/0x10 [sch_qfq]\n[   78.672148][  T363]  ? __pfx__printk+0x10/0x10\n[   78.672322][  T363]  ? srso_alias_return_thunk+0x5/0xfbef5\n[   78.672496][  T363]  ? lockdep_hardirqs_on_prepare+0xa8/0x1a0\n[   78.672706][  T363]  ? srso_alias_return_thunk+0x5/0xfbef5\n[   78.672875][  T363]  ? trace_hardirqs_on+0x19/0x1a0\n[   78.673047][  T363]  red_dequeue+0x65/0x270 [sch_red]\n[   78.673217][  T363]  ? srso_alias_return_thunk+0x5/0xfbef5\n[   78.673385][  T363]  tbf_dequeue.cold+0xb0/0x70c [sch_tbf]\n[   78.673566][  T363]  __qdisc_run+0x169/0x1900\n\nLo correcto a hacer en #1b es tomar el skb de la cola gso_skb.\nEste conjunto de parches soluciona ese problema cambiando #1b para usar el m\u00e9todo qdisc_dequeue_peeked() en su lugar."
          }
        ],
        "id": "CVE-2026-43496",
        "lastModified": "2026-07-23T16:10:00.137",
        "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"
            }
          ]
        },
        "published": "2026-05-21T13:16:18.960",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/03b0aaeba082ae981a0dfe96cdd03d02050537a1"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
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            "url": "https://git.kernel.org/stable/c/36aa34f42cb6842cf371f3a2d3e855d24fd57a50"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
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            "url": "https://git.kernel.org/stable/c/458d5615272d3de535748342eb68ca492343048c"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
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            "url": "https://git.kernel.org/stable/c/45cd83c5c470ba49fe261489c8358ad7b9df7c45"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/587dcf970a525f543d8b5855d9f37a4ca97b76ef"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
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            "url": "https://git.kernel.org/stable/c/8d09618840b99ef00154d3e731ce9b11e096196d"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/c7335f4dc0fa21f7015b910c6fc2f4d599732328"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/ce051eede433f876d322ac3550a36a3c6fc4c231"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Analyzed",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-476"
              }
            ],
            "source": "nvd@nist.gov",
            "type": "Primary"
          }
        ]
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Low",
      "current_release_date": "2026-07-02T19:46:16+00:00",
      "cve": "CVE-2026-43496",
      "id": "CVE-2026-43496",
      "initial_release_date": "2026-05-21T00:00:00+00:00",
      "product_status:known_affected": "274",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: net/sched: sch_red: Replace direct dequeue call with peek and qdisc_dequeue_peeked",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43496.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-09-11T01:17:04Z",
      "cve": "CVE-2026-43496",
      "id": "CVE-2026-43496",
      "initial_release_date": "2026-05-22T02:20:06Z",
      "product_status:first_fixed": "2",
      "product_status:known_affected": "649",
      "product_status:recommended": "277",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-43496",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-43496.json",
      "version": "13"
    }
  }
}



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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.


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.