{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "kernel/sched/core.c",
            "kernel/sched/sched.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "81f29975631db8a78651b3140ecd0f88ffafc476",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "kernel/sched/core.c",
            "kernel/sched/sched.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.1",
              "versionType": "semver"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19.1",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched/mmcid: Don\u0027t assume CID is CPU owned on mode switch\n\nShinichiro reported a KASAN UAF, which is actually an out of bounds access\nin the MMCID management code.\n\n   CPU0\t\t\t\t\t\tCPU1\n   \t\t\t\t\t\tT1 runs in userspace\n   T0: fork(T4) -\u003e Switch to per CPU CID mode\n         fixup() set MM_CID_TRANSIT on T1/CPU1\n   T4 exit()\n   T3 exit()\n   T2 exit()\n\t\t\t\t\t\tT1 exit() switch to per task mode\n\t\t\t\t\t\t ---\u003e Out of bounds access.\n\nAs T1 has not scheduled after T0 set the TRANSIT bit, it exits with the\nTRANSIT bit set. sched_mm_cid_remove_user() clears the TRANSIT bit in\nthe task and drops the CID, but it does not touch the per CPU storage.\nThat\u0027s functionally correct because a CID is only owned by the CPU when\nthe ONCPU bit is set, which is mutually exclusive with the TRANSIT flag.\n\nNow sched_mm_cid_exit() assumes that the CID is CPU owned because the\nprior mode was per CPU. It invokes mm_drop_cid_on_cpu() which clears the\nnot set ONCPU bit and then invokes clear_bit() with an insanely large\nbit number because TRANSIT is set (bit 29).\n\nPrevent that by actually validating that the CID is CPU owned in\nmm_drop_cid_on_cpu()."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-02-18T14:53:28.387Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/81f29975631db8a78651b3140ecd0f88ffafc476"
        }
      ],
      "title": "sched/mmcid: Don\u0027t assume CID is CPU owned on mode switch",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-23225",
    "datePublished": "2026-02-18T14:53:28.387Z",
    "dateReserved": "2026-01-13T15:37:45.987Z",
    "dateUpdated": "2026-02-18T14:53:28.387Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-23225\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-02-18T16:22:32.260\",\"lastModified\":\"2026-02-18T17:51:53.510\",\"vulnStatus\":\"Awaiting Analysis\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nsched/mmcid: Don\u0027t assume CID is CPU owned on mode switch\\n\\nShinichiro reported a KASAN UAF, which is actually an out of bounds access\\nin the MMCID management code.\\n\\n   CPU0\\t\\t\\t\\t\\t\\tCPU1\\n   \\t\\t\\t\\t\\t\\tT1 runs in userspace\\n   T0: fork(T4) -\u003e Switch to per CPU CID mode\\n         fixup() set MM_CID_TRANSIT on T1/CPU1\\n   T4 exit()\\n   T3 exit()\\n   T2 exit()\\n\\t\\t\\t\\t\\t\\tT1 exit() switch to per task mode\\n\\t\\t\\t\\t\\t\\t ---\u003e Out of bounds access.\\n\\nAs T1 has not scheduled after T0 set the TRANSIT bit, it exits with the\\nTRANSIT bit set. sched_mm_cid_remove_user() clears the TRANSIT bit in\\nthe task and drops the CID, but it does not touch the per CPU storage.\\nThat\u0027s functionally correct because a CID is only owned by the CPU when\\nthe ONCPU bit is set, which is mutually exclusive with the TRANSIT flag.\\n\\nNow sched_mm_cid_exit() assumes that the CID is CPU owned because the\\nprior mode was per CPU. It invokes mm_drop_cid_on_cpu() which clears the\\nnot set ONCPU bit and then invokes clear_bit() with an insanely large\\nbit number because TRANSIT is set (bit 29).\\n\\nPrevent that by actually validating that the CID is CPU owned in\\nmm_drop_cid_on_cpu().\"}],\"metrics\":{},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/81f29975631db8a78651b3140ecd0f88ffafc476\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}"
  }
}