{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "ff750311d30acc9564ef577050794953eee59f01"
            },
            {
              "fixed": "b02948a23455f8190a53887b2d2c13ae1d360cea"
            },
            {
              "fixed": "9d9c5c218ea356a1d88765214ad2919605280ab1"
            },
            {
              "fixed": "7a1c293e7aa17f1afaee0684e0e931fe23a5a6b1"
            },
            {
              "fixed": "c68e0068a236f9a7dfc19720bdf11e5d80a85089"
            },
            {
              "fixed": "88c673a0bd233df44ca0020da82f4fd3876de27a"
            },
            {
              "fixed": "0cb85377daaefb4ce5ce72975f2deb27ee0e0cad"
            },
            {
              "fixed": "e1ca4e3a380ef3e8f46ce006f1146392e3f32c98"
            },
            {
              "fixed": "1f7745fb3580152ca902ef181b605f33cabfb1d0"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.6.39"
            },
            {
              "fixed": "5.10.271"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.222"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.189"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.158"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.112"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.55"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.9"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98636.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nsquashfs: Add dictionary size range check to prevent shift-out-of-bounds\n\nWhen an abnormal SquashFS image (COMP_OPTS flag is 1 but dictionary size\nis 0) is mounted, and performs shift operations using dictionarysize, the\nshift exponent is -1, causing a shift-out-of-bounds.\n\nDetail as below:\nsquashfs_comp_opts(msblk, buffer, length)\n  squashfs_xz_comp_opts()\n    if (comp_opts)\n      n = ffs(opts-\u003edict_size) - 1;\u003c----opts-\u003edict_size=0, n=-1\n      if (opts-\u003edict_size != (1 \u003c\u003c n) \u0026\u0026 opts-\u003edict_size !=\n\t  \t(1 \u003c\u003c n) + (1 \u003c\u003c (n + 1))) \u003c----shift-out-of-bounds\n\nFix it by adding a dictionary size range check before the shift operation.",
  "id": "CVE-2026-98636",
  "modified": "2026-10-19T02:30:24.701202216Z",
  "published": "2026-10-18T15:20:07.184Z",
  "references": [
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0cb85377daaefb4ce5ce72975f2deb27ee0e0cad"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1f7745fb3580152ca902ef181b605f33cabfb1d0"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7a1c293e7aa17f1afaee0684e0e931fe23a5a6b1"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/88c673a0bd233df44ca0020da82f4fd3876de27a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9d9c5c218ea356a1d88765214ad2919605280ab1"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b02948a23455f8190a53887b2d2c13ae1d360cea"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c68e0068a236f9a7dfc19720bdf11e5d80a85089"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e1ca4e3a380ef3e8f46ce006f1146392e3f32c98"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98636.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98636"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "squashfs: Add dictionary size range check to prevent shift-out-of-bounds"
}