CVE-2026-80630 (GCVE-0-2026-80630)

Vulnerability from cvelistv5 – Published: 2026-08-28 06:48 – Updated: 2026-08-29 06:21
VLAI
Title
net/sched: sch_fq_codel: Do not call qdisc_tree_reduce_backlog during peek before restoring qlen
Summary
In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_fq_codel: Do not call qdisc_tree_reduce_backlog during peek before restoring qlen Whenever fq_codel drops packets during peek, it calls qdisc_tree_reduce_backlog. An issue arises because it calls qdisc_tree_reduce_backlog before it reincrements the qlen. If qlen drops to zero, but peek returns an skb, the parent's qlen_notify callback will be executed even though fq_codel still has 1 packet on the queue and, thus, will mistakenly deactivate the parent's class causing issues like a recent report [1] and a wild memory access in qfq: [ 29.371146][ T360] Oops: general protection fault, probably for non-canonical address 0xfbd59c0000000024: 0000 [#1] SMP KASAN NOPTI [ 29.371666][ T360] KASAN: maybe wild-memory-access in range [0xdead000000000120-0xdead000000000127] [ 29.371987][ T360] CPU: 6 UID: 0 PID: 360 Comm: tc Not tainted 7.1.0-rc5-00285-gc530e5b2dbc6-dirty #82 PREEMPT(full) [ 29.372384][ T360] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 29.372620][ T360] RIP: 0010:qfq_deactivate_agg (include/linux/list.h:1029 (discriminator 2) include/linux/list.h:1043 (discriminator 2) net/sched/sch_qfq.c:1369 (discriminator 2) net/sched/sch_qfq.c:1395 (discriminator 2)) sch_qfq [ 29.373544][ T360] RSP: 0018:ffff888102417370 EFLAGS: 00010216 [ 29.373800][ T360] RAX: 0000000000000000 RBX: ffff88811224d568 RCX: dffffc0000000000 [ 29.374079][ T360] RDX: 1ffff11021fe1543 RSI: ffff88810ff0aa00 RDI: dffffc0000000000 [ 29.374368][ T360] RBP: ffff88811224c280 R08: dead000000000122 R09: 1bd5a00000000024 [ 29.374649][ T360] R10: fffffbfff7940329 R11: fffffbfff7940329 R12: 0000000000000000 [ 29.374926][ T360] R13: dead000000000100 R14: ffff88811224d580 R15: ffff88811224d578 [ 29.375207][ T360] FS: 00007f5b794e5780(0000) GS:ffff88815d1e9000(0000) knlGS:0000000000000000 [ 29.375545][ T360] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 29.375823][ T360] CR2: 000055ffb091f000 CR3: 000000010a305000 CR4: 0000000000750ef0 [ 29.376103][ T360] PKRU: 55555554 [ 29.376258][ T360] Call Trace: [ 29.376401][ T360] <TASK> ... [ 29.376885][ T360] qfq_reset_qdisc (net/sched/sch_qfq.c:357 net/sched/sch_qfq.c:1487) sch_qfq [ 29.377074][ T360] qdisc_reset (net/sched/sch_generic.c:1057) [ 29.377414][ T360] __qdisc_destroy (net/sched/sch_generic.c:1096) [ 29.377600][ T360] qdisc_graft (net/sched/sch_api.c:1062 net/sched/sch_api.c:1053 net/sched/sch_api.c:1159) [ 29.378593][ T360] tc_get_qdisc (net/sched/sch_api.c:1528 net/sched/sch_api.c:1556) Fix this by only calling qdisc_tree_reduce_backlog in peek after the qlen is restored. [1] http://lore.kernel.org/netdev/CAN2cbVe79oj0O9==m4+4x3v+O+qzRagA=2=wkrp9i9=CqYvyZA@mail.gmail.com/
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: cc71a757da78dd4aa1b4a9b19cb011833730ccf2 , < 3e515188393e62a718ccebee651ee74514104ff6 (git)
Affected: eda741fe155ddf5ecd2dd3bfbd4fc3c0c7dbb450 , < 20dd591d8f951e1e6aca5052be8785e6181055e2 (git)
Affected: 829c49b6b2ff45b043739168fd1245e4e1a91a30 , < 94a5f1efdefb01f82cd228bf4e7ef1e8fc075c80 (git)
Affected: 2f9761a94bae33d26e6a81b31b36e7d776d93dc1 , < acc08a0c7f37ebb1901144e03a7cba7d4afd9203 (git)
Affected: 4d55144b12e742404bb3f8fee6038bafbf45619d , < 7c09843fd2b44d9bf0de798683861d1aecd62a08 (git)
Affected: 342debc12183b51773b3345ba267e9263bdfaaef , < 0500af8630c3253f0dde879bd3a73a06bb2f2b3f (git)
Affected: 342debc12183b51773b3345ba267e9263bdfaaef , < af54df2f44d9605614bc7ed96640302a240a9a62 (git)
Affected: 342debc12183b51773b3345ba267e9263bdfaaef , < 097f6fc7b1ae362dd7a9444b2572162fda73b284 (git)
Affected: 7a742a9506849d1c1aa71e36c89855ceddc7d58e (git)
Affected: e73c838c80dccb9e4f19becc11d9f3cb4a27d483 (git)
Affected: a57fe60ef4cf96bfbb6b58397ec28bdb5a5c6b31 (git)
Affected: 5.10.241 , < 5.10.261 (semver)
Affected: 5.15.190 , < 5.15.212 (semver)
Affected: 6.1.135 , < 6.1.178 (semver)
Affected: 6.6.88 , < 6.6.145 (semver)
Affected: 6.12.24 , < 6.12.97 (semver)
Affected: 5.4.297 , < 5.5 (semver)
Affected: 6.13.12 , < 6.14 (semver)
Affected: 6.14.3 , < 6.15 (semver)
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Linux Linux Affected: 6.15
Unaffected: 0 , < 6.15 (semver)
Unaffected: 5.10.261 , ≤ 5.10.* (semver)
Unaffected: 5.15.212 , ≤ 5.15.* (semver)
Unaffected: 6.1.178 , ≤ 6.1.* (semver)
Unaffected: 6.6.145 , ≤ 6.6.* (semver)
Unaffected: 6.12.97 , ≤ 6.12.* (semver)
Unaffected: 6.18.40 , ≤ 6.18.* (semver)
Unaffected: 7.1.5 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
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      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sch_fq_codel: Do not call qdisc_tree_reduce_backlog during peek before restoring qlen\n\nWhenever fq_codel drops packets during peek, it calls\nqdisc_tree_reduce_backlog. An issue arises because it calls\nqdisc_tree_reduce_backlog before it reincrements the qlen. If qlen drops\nto zero, but peek returns an skb, the parent\u0027s qlen_notify callback will be\nexecuted even though fq_codel still has 1 packet on the queue and, thus,\nwill mistakenly deactivate the parent\u0027s class causing issues like a recent\nreport [1] and a wild memory access in qfq:\n\n[   29.371146][  T360] Oops: general protection fault, probably for non-canonical address 0xfbd59c0000000024: 0000 [#1] SMP KASAN NOPTI\n[   29.371666][  T360] KASAN: maybe wild-memory-access in range [0xdead000000000120-0xdead000000000127]\n[   29.371987][  T360] CPU: 6 UID: 0 PID: 360 Comm: tc Not tainted 7.1.0-rc5-00285-gc530e5b2dbc6-dirty #82 PREEMPT(full)\n[   29.372384][  T360] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011\n[   29.372620][  T360] RIP: 0010:qfq_deactivate_agg (include/linux/list.h:1029 (discriminator 2) include/linux/list.h:1043 (discriminator 2) net/sched/sch_qfq.c:1369 (discriminator 2) net/sched/sch_qfq.c:1395 (discriminator 2)) sch_qfq\n[   29.373544][  T360] RSP: 0018:ffff888102417370 EFLAGS: 00010216\n[   29.373800][  T360] RAX: 0000000000000000 RBX: ffff88811224d568 RCX: dffffc0000000000\n[   29.374079][  T360] RDX: 1ffff11021fe1543 RSI: ffff88810ff0aa00 RDI: dffffc0000000000\n[   29.374368][  T360] RBP: ffff88811224c280 R08: dead000000000122 R09: 1bd5a00000000024\n[   29.374649][  T360] R10: fffffbfff7940329 R11: fffffbfff7940329 R12: 0000000000000000\n[   29.374926][  T360] R13: dead000000000100 R14: ffff88811224d580 R15: ffff88811224d578\n[   29.375207][  T360] FS:  00007f5b794e5780(0000) GS:ffff88815d1e9000(0000) knlGS:0000000000000000\n[   29.375545][  T360] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[   29.375823][  T360] CR2: 000055ffb091f000 CR3: 000000010a305000 CR4: 0000000000750ef0\n[   29.376103][  T360] PKRU: 55555554\n[   29.376258][  T360] Call Trace:\n[   29.376401][  T360]  \u003cTASK\u003e\n...\n[   29.376885][  T360] qfq_reset_qdisc (net/sched/sch_qfq.c:357 net/sched/sch_qfq.c:1487) sch_qfq\n[   29.377074][  T360]  qdisc_reset (net/sched/sch_generic.c:1057)\n[   29.377414][  T360]  __qdisc_destroy (net/sched/sch_generic.c:1096)\n[   29.377600][  T360]  qdisc_graft (net/sched/sch_api.c:1062 net/sched/sch_api.c:1053 net/sched/sch_api.c:1159)\n[   29.378593][  T360]  tc_get_qdisc (net/sched/sch_api.c:1528 net/sched/sch_api.c:1556)\n\nFix this by only calling qdisc_tree_reduce_backlog in peek after the\nqlen is restored.\n\n[1] http://lore.kernel.org/netdev/CAN2cbVe79oj0O9==m4+4x3v+O+qzRagA=2=wkrp9i9=CqYvyZA@mail.gmail.com/"
        }
      ],
      "metrics": [
        {
          "cvssV3_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",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - Remote senders reach the bug when packets traverse a QFQ or other qlen_notify parent with an fq_codel child: qfq_enqueue() and qfq_dequeue() call the child peek handler during __dev_queue_xmit egress scheduling, and CoDel can drop there before qlen is restored.\nAC:L - The attacker controls traffic rate, packet size, and CoDel drop behavior to force drops during peek while qlen reads zero; this is a deterministic logic bug, not a race on uncontrollable kernel state or a rare compile-time configuration.\nPR:N - On systems where an operator has already deployed a parent qdisc with an fq_codel leaf, any remote party that can send packets into the shaped class can trigger the faulty peek/drop path with no account or capabilities on the victim host.\nUI:N - Exploitation requires only attacker-generated traffic to drive peek-time CoDel drops through the installed hierarchy; no independent action by another user or administrator is needed at trigger time.\nS:U - The flaw corrupts in-kernel QFQ/fq_codel scheduler structures and memory within the same kernel security domain; it does not cross VM, container, or IOMMU authority boundaries.\nC:H - False qlen_notify prematurely deactivates QFQ aggregates while packets remain; the fix commit shows KASAN wild-memory-access on poisoned aggregate list nodes in qfq_deactivate_agg(), giving attacker-influenced reads from freed/corrupted scheduler memory.\nI:H - Corrupted aggregate/class linkage leads to invalid hlist operations and inconsistent scheduler state that can be steered with heap layout control, yielding memory corruption primitives usable for arbitrary kernel writes or control-flow hijack.\nA:H - The published oops is a general protection fault from corrupted QFQ state during qdisc teardown, and the same corruption during live packet scheduling can reliably kernel-panic or hang affected hosts."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-29T06:21:30.275Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/3e515188393e62a718ccebee651ee74514104ff6"
        },
        {
          "url": "https://git.kernel.org/stable/c/20dd591d8f951e1e6aca5052be8785e6181055e2"
        },
        {
          "url": "https://git.kernel.org/stable/c/94a5f1efdefb01f82cd228bf4e7ef1e8fc075c80"
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          "url": "https://git.kernel.org/stable/c/acc08a0c7f37ebb1901144e03a7cba7d4afd9203"
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        },
        {
          "url": "https://git.kernel.org/stable/c/af54df2f44d9605614bc7ed96640302a240a9a62"
        },
        {
          "url": "https://git.kernel.org/stable/c/097f6fc7b1ae362dd7a9444b2572162fda73b284"
        }
      ],
      "title": "net/sched: sch_fq_codel: Do not call qdisc_tree_reduce_backlog during peek before restoring qlen",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
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  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-80630",
    "datePublished": "2026-08-28T06:48:46.569Z",
    "dateReserved": "2026-08-26T14:34:25.776Z",
    "dateUpdated": "2026-08-29T06:21:30.275Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
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      "date": "2026-09-21",
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                    "lessThan": "20dd591d8f951e1e6aca5052be8785e6181055e2",
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                    "version": "eda741fe155ddf5ecd2dd3bfbd4fc3c0c7dbb450",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "94a5f1efdefb01f82cd228bf4e7ef1e8fc075c80",
                    "status": "affected",
                    "version": "829c49b6b2ff45b043739168fd1245e4e1a91a30",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "acc08a0c7f37ebb1901144e03a7cba7d4afd9203",
                    "status": "affected",
                    "version": "2f9761a94bae33d26e6a81b31b36e7d776d93dc1",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "7c09843fd2b44d9bf0de798683861d1aecd62a08",
                    "status": "affected",
                    "version": "4d55144b12e742404bb3f8fee6038bafbf45619d",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "0500af8630c3253f0dde879bd3a73a06bb2f2b3f",
                    "status": "affected",
                    "version": "342debc12183b51773b3345ba267e9263bdfaaef",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "af54df2f44d9605614bc7ed96640302a240a9a62",
                    "status": "affected",
                    "version": "342debc12183b51773b3345ba267e9263bdfaaef",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "097f6fc7b1ae362dd7a9444b2572162fda73b284",
                    "status": "affected",
                    "version": "342debc12183b51773b3345ba267e9263bdfaaef",
                    "versionType": "git"
                  },
                  {
                    "status": "affected",
                    "version": "7a742a9506849d1c1aa71e36c89855ceddc7d58e",
                    "versionType": "git"
                  },
                  {
                    "status": "affected",
                    "version": "e73c838c80dccb9e4f19becc11d9f3cb4a27d483",
                    "versionType": "git"
                  },
                  {
                    "status": "affected",
                    "version": "a57fe60ef4cf96bfbb6b58397ec28bdb5a5c6b31",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "5.10.261",
                    "status": "affected",
                    "version": "5.10.241",
                    "versionType": "semver"
                  },
                  {
                    "lessThan": "5.15.212",
                    "status": "affected",
                    "version": "5.15.190",
                    "versionType": "semver"
                  },
                  {
                    "lessThan": "6.1.178",
                    "status": "affected",
                    "version": "6.1.135",
                    "versionType": "semver"
                  },
                  {
                    "lessThan": "6.6.145",
                    "status": "affected",
                    "version": "6.6.88",
                    "versionType": "semver"
                  },
                  {
                    "lessThan": "6.12.97",
                    "status": "affected",
                    "version": "6.12.24",
                    "versionType": "semver"
                  },
                  {
                    "lessThan": "5.5",
                    "status": "affected",
                    "version": "5.4.297",
                    "versionType": "semver"
                  },
                  {
                    "lessThan": "6.14",
                    "status": "affected",
                    "version": "6.13.12",
                    "versionType": "semver"
                  },
                  {
                    "lessThan": "6.15",
                    "status": "affected",
                    "version": "6.14.3",
                    "versionType": "semver"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
                  "net/sched/sch_fq_codel.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "status": "affected",
                    "version": "6.15"
                  },
                  {
                    "lessThan": "6.15",
                    "status": "unaffected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.10.*",
                    "status": "unaffected",
                    "version": "5.10.261",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.15.*",
                    "status": "unaffected",
                    "version": "5.15.212",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.1.*",
                    "status": "unaffected",
                    "version": "6.1.178",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.6.*",
                    "status": "unaffected",
                    "version": "6.6.145",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.12.*",
                    "status": "unaffected",
                    "version": "6.12.97",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.18.*",
                    "status": "unaffected",
                    "version": "6.18.40",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "7.1.*",
                    "status": "unaffected",
                    "version": "7.1.5",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "7.2",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sch_fq_codel: Do not call qdisc_tree_reduce_backlog during peek before restoring qlen\n\nWhenever fq_codel drops packets during peek, it calls\nqdisc_tree_reduce_backlog. An issue arises because it calls\nqdisc_tree_reduce_backlog before it reincrements the qlen. If qlen drops\nto zero, but peek returns an skb, the parent\u0027s qlen_notify callback will be\nexecuted even though fq_codel still has 1 packet on the queue and, thus,\nwill mistakenly deactivate the parent\u0027s class causing issues like a recent\nreport [1] and a wild memory access in qfq:\n\n[   29.371146][  T360] Oops: general protection fault, probably for non-canonical address 0xfbd59c0000000024: 0000 [#1] SMP KASAN NOPTI\n[   29.371666][  T360] KASAN: maybe wild-memory-access in range [0xdead000000000120-0xdead000000000127]\n[   29.371987][  T360] CPU: 6 UID: 0 PID: 360 Comm: tc Not tainted 7.1.0-rc5-00285-gc530e5b2dbc6-dirty #82 PREEMPT(full)\n[   29.372384][  T360] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011\n[   29.372620][  T360] RIP: 0010:qfq_deactivate_agg (include/linux/list.h:1029 (discriminator 2) include/linux/list.h:1043 (discriminator 2) net/sched/sch_qfq.c:1369 (discriminator 2) net/sched/sch_qfq.c:1395 (discriminator 2)) sch_qfq\n[   29.373544][  T360] RSP: 0018:ffff888102417370 EFLAGS: 00010216\n[   29.373800][  T360] RAX: 0000000000000000 RBX: ffff88811224d568 RCX: dffffc0000000000\n[   29.374079][  T360] RDX: 1ffff11021fe1543 RSI: ffff88810ff0aa00 RDI: dffffc0000000000\n[   29.374368][  T360] RBP: ffff88811224c280 R08: dead000000000122 R09: 1bd5a00000000024\n[   29.374649][  T360] R10: fffffbfff7940329 R11: fffffbfff7940329 R12: 0000000000000000\n[   29.374926][  T360] R13: dead000000000100 R14: ffff88811224d580 R15: ffff88811224d578\n[   29.375207][  T360] FS:  00007f5b794e5780(0000) GS:ffff88815d1e9000(0000) knlGS:0000000000000000\n[   29.375545][  T360] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[   29.375823][  T360] CR2: 000055ffb091f000 CR3: 000000010a305000 CR4: 0000000000750ef0\n[   29.376103][  T360] PKRU: 55555554\n[   29.376258][  T360] Call Trace:\n[   29.376401][  T360]  \u003cTASK\u003e\n...\n[   29.376885][  T360] qfq_reset_qdisc (net/sched/sch_qfq.c:357 net/sched/sch_qfq.c:1487) sch_qfq\n[   29.377074][  T360]  qdisc_reset (net/sched/sch_generic.c:1057)\n[   29.377414][  T360]  __qdisc_destroy (net/sched/sch_generic.c:1096)\n[   29.377600][  T360]  qdisc_graft (net/sched/sch_api.c:1062 net/sched/sch_api.c:1053 net/sched/sch_api.c:1159)\n[   29.378593][  T360]  tc_get_qdisc (net/sched/sch_api.c:1528 net/sched/sch_api.c:1556)\n\nFix this by only calling qdisc_tree_reduce_backlog in peek after the\nqlen is restored.\n\n[1] http://lore.kernel.org/netdev/CAN2cbVe79oj0O9==m4+4x3v+O+qzRagA=2=wkrp9i9=CqYvyZA@mail.gmail.com/"
          }
        ],
        "id": "CVE-2026-80630",
        "lastModified": "2026-08-29T07:16:47.027",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "HIGH",
                "baseScore": 9.8,
                "baseSeverity": "CRITICAL",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "HIGH",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 3.9,
              "impactScore": 5.9,
              "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
              "type": "Secondary"
            }
          ]
        },
        "published": "2026-08-28T08:16:47.850",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/0500af8630c3253f0dde879bd3a73a06bb2f2b3f"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/097f6fc7b1ae362dd7a9444b2572162fda73b284"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/20dd591d8f951e1e6aca5052be8785e6181055e2"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/3e515188393e62a718ccebee651ee74514104ff6"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/7c09843fd2b44d9bf0de798683861d1aecd62a08"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/94a5f1efdefb01f82cd228bf4e7ef1e8fc075c80"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/acc08a0c7f37ebb1901144e03a7cba7d4afd9203"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/af54df2f44d9605614bc7ed96640302a240a9a62"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Received"
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-09-01T12:36:55+00:00",
      "cve": "CVE-2026-80630",
      "id": "CVE-2026-80630",
      "initial_release_date": "2026-08-28T00:00:00+00:00",
      "product_status:known_affected": "260",
      "product_status:known_not_affected": "14",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: net/sched: sch_fq_codel: Do not call qdisc_tree_reduce_backlog during peek before restoring qlen",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80630.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-09-15T01:10:32Z",
      "cve": "CVE-2026-80630",
      "id": "CVE-2026-80630",
      "initial_release_date": "2026-08-28T16:35:48Z",
      "product_status:known_affected": "316",
      "product_status:known_not_affected": "37",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-80630",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-80630.json",
      "version": "7"
    }
  }
}



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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.


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.