{
  "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-2026-45990",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-45990",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-05-27T12:55:42.572Z",
    "updatedAt": "2026-06-14T17:46:45.762Z",
    "importedAt": "2026-10-24T01:58:14.884Z",
    "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": "slub: fix data loss and overflow in krealloc()",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nslub: fix data loss and overflow in krealloc()\n\nCommit 2cd8231796b5 (\"mm/slub: allow to set node and align in\nk[v]realloc\") introduced the ability to force a reallocation if the\noriginal object does not satisfy new alignment or NUMA node, even when\nthe object is being shrunk.\n\nThis introduced two bugs in the reallocation fallback path:\n\n1. Data loss during NUMA migration: The jump to 'alloc_new' happens\n   before 'ks' and 'orig_size' are initialized. As a result, the\n   memcpy() in the 'alloc_new' block would copy 0 bytes into the new\n   allocation.\n\n2. Buffer overflow during shrinking: When shrinking an object while\n   forcing a new alignment, 'new_size' is smaller than the old size.\n   However, the memcpy() used the old size ('orig_size ?: ks'), leading\n   to an out-of-bounds write.\n\nThe same overflow bug exists in the kvrealloc() fallback path, where the\nold bucket size ksize(p) is copied into the new buffer without being\nbounded by the new size.\n\nA simple reproducer:\n\n\t// e.g. add to lkdtm as KREALLOC_SHRINK_OVERFLOW\n\twhile (1) {\n\t\tvoid *p = kmalloc(128, GFP_KERNEL);\n\t\tp = krealloc_node_align(p, 64, 256, GFP_KERNEL, NUMA_NO_NODE);\n\t\tkfree(p);\n\t}\n\ndemonstrates the issue:\n\n  ==================================================================\n  BUG: KFENCE: out-of-bounds write in memcpy_orig+0x68/0x130\n\n  Out-of-bounds write at 0xffff8883ad757038 (120B right of kfence-#47):\n   memcpy_orig+0x68/0x130\n   krealloc_node_align_noprof+0x1c8/0x340\n   lkdtm_KREALLOC_SHRINK_OVERFLOW+0x8c/0xc0 [lkdtm]\n   lkdtm_do_action+0x3a/0x60 [lkdtm]\n   ...\n\n  kfence-#47: 0xffff8883ad756fc0-0xffff8883ad756fff, size=64, cache=kmalloc-64\n\n  allocated by task 316 on cpu 7 at 97.680481s (0.021813s ago):\n   krealloc_node_align_noprof+0x19c/0x340\n   lkdtm_KREALLOC_SHRINK_OVERFLOW+0x8c/0xc0 [lkdtm]\n   lkdtm_do_action+0x3a/0x60 [lkdtm]\n   ...\n  ==================================================================\n\nFix it by moving the old size calculation to the top of __do_krealloc()\nand bounding all copy lengths by the new allocation size.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "2cd8231796b5e7133b1c3d66ad7d2a3c42c97258",
              "status": "affected",
              "versionType": "git",
              "lessThan": "38387ccc0fbe38d14fb4c2ad7ee1d7404e5e59fd"
            },
            {
              "version": "2cd8231796b5e7133b1c3d66ad7d2a3c42c97258",
              "status": "affected",
              "versionType": "git",
              "lessThan": "550fa6b5aabb096554536ac1e3ec96b76cbb35fd"
            },
            {
              "version": "2cd8231796b5e7133b1c3d66ad7d2a3c42c97258",
              "status": "affected",
              "versionType": "git",
              "lessThan": "082a6d03a2d685a83a332666b500ad3966349588"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "6.18",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "6.18"
            },
            {
              "version": "6.18.27",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "version": "7.0.4",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "7.0.*"
            },
            {
              "version": "7.1",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}