{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "7c65ae81ea86a6ed8086e1a5651acd766187f19b"
            },
            {
              "fixed": "2907e9d0f05b506dfd58aec589a23042a56ef36b"
            },
            {
              "fixed": "e2f188cdbf8312289532c36eb4e9eb1c9544d43a"
            },
            {
              "fixed": "b7d9c359e5cf867f7eb23df3bb1c6b9e58af24da"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.12.0"
            },
            {
              "fixed": "6.18.42"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.1.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68421.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched_ext: Don't warn on core-sched forced idle in put_prev_task_scx()\n\nput_prev_task_scx() warns when a runnable task drops to a lower sched_class\nwithout SCX_OPS_ENQ_LAST, on the assumption that balance_one() would have\nkept it running. Core scheduling breaks that: a forced-idle SMT sibling\nreschedules through the core_pick fast path in pick_next_task(), which skips\npick_task_scx() and thus balance_one(), so a runnable task can drop to idle\nwith ENQ_LAST unset.\n\nGate the warning on sched_cpu_cookie_match(): a cookie mismatch means core\nscheduling forced the idle, while a match (or core scheduling off) still\ncatches a genuine missing-ENQ_LAST drop.",
  "id": "CVE-2026-68421",
  "modified": "2026-08-18T03:31:13.961463457Z",
  "published": "2026-08-10T12:04:41.946Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2907e9d0f05b506dfd58aec589a23042a56ef36b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b7d9c359e5cf867f7eb23df3bb1c6b9e58af24da"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e2f188cdbf8312289532c36eb4e9eb1c9544d43a"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68421.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-68421"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "sched_ext: Don't warn on core-sched forced idle in put_prev_task_scx()"
}