{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "320d031ad6e4d67e8e1ab08ac71efda02bc85683"
            },
            {
              "fixed": "86cf2eba2056bcf9c41fba260e599bd95bf9943b"
            },
            {
              "fixed": "3042add80c2c50bd127d570b83319af612efde65"
            },
            {
              "fixed": "478ed6b7d2577439c610f91fa8759a4c878a4264"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.17.0"
            },
            {
              "fixed": "6.18.33"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.0.10"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/52xxx/CVE-2026-52997.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sch_dualpi2: drain both C-queue and L-queue in dualpi2_change()\n\nFix dualpi2_change() to correctly enforce updated limit and memlimit\nvalues after a configuration change of the dualpi2 qdisc.\n\nBefore this patch, dualpi2_change() always attempted to dequeue packets\nvia the root qdisc (C-queue) when reducing backlog or memory usage, and\nunconditionally assumed that a valid skb will be returned. When traffic\nclassification results in packets being queued in the L-queue while the\nC-queue is empty, this leads to a NULL skb dereference during limit or\nmemlimit enforcement.\n\nThis is fixed by first dequeuing from the C-queue path if it is\nnon-empty. Once the C-queue is empty, packets are dequeued directly from\nthe L-queue. Return values from qdisc_dequeue_internal() are checked for\nboth queues. When dequeuing from the L-queue, the parent qdisc qlen and\nbacklog counters are updated explicitly to keep overall qdisc statistics\nconsistent.",
  "id": "CVE-2026-52997",
  "modified": "2026-07-08T05:36:43.839566854Z",
  "published": "2026-06-24T16:29:09.997Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3042add80c2c50bd127d570b83319af612efde65"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/478ed6b7d2577439c610f91fa8759a4c878a4264"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/86cf2eba2056bcf9c41fba260e599bd95bf9943b"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/52xxx/CVE-2026-52997.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-52997"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.7.5",
  "summary": "net/sched: sch_dualpi2: drain both C-queue and L-queue in dualpi2_change()"
}