{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "c74443d92f68f07c03ae242ced554b749e6c6736"
            },
            {
              "fixed": "64aa1bb4017d598828c6d8cd718f43daf2a83375"
            },
            {
              "fixed": "174f0582e38abe03b88e15f04bfe58490f88cb19"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.11.0"
            },
            {
              "fixed": "7.2.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/93xxx/CVE-2026-93181.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nperf/x86/intel/uncore: Fix uncore_box ref/unref ordering\n\nIn uncore_event_cpu_online(), uncore_box_ref() was called before\nuncore_change_context().  uncore_box_ref() gates on box-\u003ecpu \u003e= 0,\nbut box-\u003ecpu is still -1 at that point because uncore_change_context()\nhas not run yet.  As a result, the box is never initialized on the\nfirst CPU to come online in a die, leaving it permanently\nuninitialized in the single-CPU-per-die case.\n\nThus, box-\u003erefcnt is one count below the true value, and in the CPU\noffline path, the box will be torn down on the second-to-last CPU.\n\nIn uncore_event_cpu_offline(), uncore_box_unref() was called after\nuncore_change_context(), so box-\u003ecpu is already -1 when the collector\nCPU goes offline, which prevents it from tearing down the box.\n\nFix by swapping the call order in both paths so that\nuncore_box_{ref,unref}() runs at the point where box-\u003ecpu reflects\nthe correct context.\n\nMove allocate_boxes() out of uncore_box_ref() to enable this\nreordering.",
  "id": "CVE-2026-93181",
  "modified": "2026-09-19T03:30:18.669549099Z",
  "published": "2026-09-17T16:12:08.716Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/174f0582e38abe03b88e15f04bfe58490f88cb19"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/64aa1bb4017d598828c6d8cd718f43daf2a83375"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/93xxx/CVE-2026-93181.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-93181"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "perf/x86/intel/uncore: Fix uncore_box ref/unref ordering"
}