{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2026-93253",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-93253",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-09-24T15:51:29.259Z",
    "updatedAt": "2026-10-19T09:08:06.840Z",
    "importedAt": "2026-10-24T01:58:35.090Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "sched/isolation: Defer freeing of cpumask memblock memory to initcall",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched/isolation: Defer freeing of cpumask memblock memory to initcall\n\nWhen testing a linux-next kernel with commit 59bd1d914bb5 (\"memblock:\nwarn when freeing reserved memory before memory map is initialized\"),\nthe following warning was hit when there was a \"nohz_full\" kernel boot\nparameter.\n\n  Cannot free reserved memory because of deferred initialization of the memory map\n  WARNING: mm/memblock.c:904 at __free_reserved_area+0xde/0xf0, CPU#0: swapper/0/0\n    :\n  Call Trace:\n   <TASK>\n   memblock_phys_free+0xcb/0x100\n   housekeeping_init+0x14c/0x170\n   start_kernel+0x207/0x450\n   x86_64_start_reservations+0x24/0x30\n   x86_64_start_kernel+0xda/0xe0\n   common_startup_64+0x13e/0x141\n   </TASK>\n\nIOW, we shouldn't free memblock allocated memory so early\nin the boot process when memory map isn't fully initialized in\ndeferred_init_memmap().\n\nFix it by saving the housekeeping cpumask memblock memory to be\nfreed into a llist free list in housekeeping_init() and add a new\nhousekeeping_late_init() helper to defer the actual freeing of memblock\nmemory to when initcall's are being processed. The cpumask memblock\nmemory is treated as a llist_node with the size of a \"long\" type which\nis also smallest cpumask size that can be allocated.\n\nThe non-atomic version of the llist APIs are used as there is no\ncontention.\n\nThis commit depends on the presence of commit 7c2eee9c1367 (\"memblock:\ndon't touch memblock arrays when memblock_free() is called late\")\nto prevent a KASAN UAF bug report [1].\n\n [1] https://lore.kernel.org/lkml/20260505051821.1107133-1-longman@redhat.com/",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "27c3a5967f054ab666704cb28f2aeb18ca07cab7",
              "status": "affected",
              "versionType": "git",
              "lessThan": "811fdac2d1bdf0b0d3fda262aac288ddd13a1422"
            },
            {
              "version": "27c3a5967f054ab666704cb28f2aeb18ca07cab7",
              "status": "affected",
              "versionType": "git",
              "lessThan": "2b58c749b8c5244e259a0230bc57b10b010dc545"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "7.0",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "7.0"
            },
            {
              "version": "7.2.6",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "7.2.*"
            },
            {
              "version": "7.3",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}