net/sched: sch_multiq: Replace direct dequeue call with peek and qdisc_dequeue_peeked

{
  "id": "2d54c59f3c035512183a33a614f17d8278b5a8af607abffb7fd495a208e57cd5",
  "url": "https://osv.dev/vulnerability/CVE-2026-72036",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "net/sched: sch_multiq: Replace direct dequeue call with peek and qdisc_dequeue_peeked",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_multiq: Replace direct dequeue call with peek and qdisc_dequeue_peeked multiq_dequeue() takes a packet from a band's child with a direct ->dequeue() call after multiq_peek() peeked it. When the child is non-work-conserving the peek stashes the skb in the child's gso_skb, so the direct dequeue returns a different skb and orphans the stash, desyncing the child's qlen/backlog. With a qfq child reached through a peeking parent (e.g. tbf) this re-enters the child on an emptied list and dereferences NULL, panicking the kernel from softirq on ordinary egress. Take the packet through qdisc_dequeue_peeked(), as sch_prio already does and as sch_red and sch_sfb were just fixed to do. The helper is a no-op when the child has no stash, so a work-conserving child is unaffected.",
    "evidence": "osv:CVE-2026-72036",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.10.261",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "5.15.212",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.1.178",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.6.145",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.12.97",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.18.40",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "7.1.5",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-72036",
      "aliases": [
        "CVE-2026-72036"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "77be155cba4e163e8bba9fd27222a8b6189ec4f7"
                },
                {
                  "fixed": "3e5fd9d14f2d228e7260251f2e4a1d41ba8f705a"
                },
                {
                  "fixed": "eb1a9637f0bd84b5db8803af65dfb1f44785406f"
                },
                {
                  "fixed": "7a5a1582710981ef6637de9f074a60a5b1d63222"
                },
                {
                  "fixed": "86a61e46a1919e8abf4d227c204773dabb24068a"
                },
                {
                  "fixed": "1b9cc255e8089606b92b2adf504e334573682821"
                },
                {
                  "fixed": "5889064919a1e5c0a9469c54895000414fc46944"
                },
                {
                  "fixed": "fffeb2ab5eeb823d4c2330571a098f63237c9049"
                },
                {
                  "fixed": "54f6b0c843e228d499eb4b6bbb89df68cad9ad5d"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-72036.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "2.6.29"
                },
                {
                  "fixed": "5.10.261"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.11.0"
                },
                {
                  "fixed": "5.15.212"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.16.0"
                },
                {
                  "fixed": "6.1.178"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.2.0"
                },
                {
                  "fixed": "6.6.145"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.7.0"
                },
                {
                  "fixed": "6.12.97"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.13.0"
                },
                {
                  "fixed": "6.18.40"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.19.0"
                },
                {
                  "fixed": "7.1.5"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-72036.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:50.891114340Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/1b9cc255e8089606b92b2adf504e334573682821",
        "https://git.kernel.org/stable/c/3e5fd9d14f2d228e7260251f2e4a1d41ba8f705a",
        "https://git.kernel.org/stable/c/54f6b0c843e228d499eb4b6bbb89df68cad9ad5d",
        "https://git.kernel.org/stable/c/5889064919a1e5c0a9469c54895000414fc46944",
        "https://git.kernel.org/stable/c/7a5a1582710981ef6637de9f074a60a5b1d63222",
        "https://git.kernel.org/stable/c/86a61e46a1919e8abf4d227c204773dabb24068a",
        "https://git.kernel.org/stable/c/eb1a9637f0bd84b5db8803af65dfb1f44785406f",
        "https://git.kernel.org/stable/c/fffeb2ab5eeb823d4c2330571a098f63237c9049",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/72xxx/CVE-2026-72036.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-72036",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/72xxx/CVE-2026-72036.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-72036",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 519514,
  "published_at": "2026-08-15T05:51:57.012+00:00"
}