In the Linux kernel, the following vulnerability has been resolved: ufs: validate cylinder group...

{
  "credits": [],
  "cve_id": "CVE-2026-97926",
  "cvss": {
    "score": 7.0,
    "vector_string": "CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H"
  },
  "cvss_severities": {
    "cvss_v3": {
      "score": 7.0,
      "vector_string": "CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H"
    },
    "cvss_v4": {
      "score": 0.0,
      "vector_string": null
    }
  },
  "cwes": [],
  "description": "In the Linux kernel, the following vulnerability has been resolved:\n\nufs: validate cylinder group metadata before caching it\n\nufs_read_cylinder() copies the cylinder group index and the rotor\npositions straight from the on-disk group and caches them without any\ncheck:\n\n\tucpi->c_cgx    = fs32_to_cpu(sb, ucg->cg_cgx);\n\tucpi->c_rotor  = fs32_to_cpu(sb, ucg->cg_rotor);\n\tucpi->c_frotor = fs32_to_cpu(sb, ucg->cg_frotor);\n\tucpi->c_irotor = fs32_to_cpu(sb, ucg->cg_irotor);\n\nThey are then used as indices during allocation and free:\n\n  - c_cgx indexes the cylinder summary array as\n    UFS_SB(sb)->fs_cs(ucpi->c_cgx), so a value past s_ncg writes a 32\n    bit count outside the s_csp allocation.\n\n  - c_frotor becomes a bitmap scan start, start = c_frotor >> 3, and\n    then length = ((s_fpg + 7) >> 3) - start. A start beyond the block\n    bitmap wraps the unsigned length to a huge value, so ubh_scanc()\n    walks far past the cylinder group buffers. c_irotor drives the\n    inode bitmap the same way.\n\nA crafted image can set any of these freely, turning an ordinary\nallocation into an out of bounds access.\n\nReject a cylinder group whose recorded index does not match the group\nbeing read, or whose rotors fall outside the group, before the metadata\nis cached. Valid filesystems keep cg_cgx equal to the group number and\nthe rotors within the group, so only malformed images are rejected.",
  "epss": {
    "percentage": 0.00154,
    "percentile": 0.03802
  },
  "ghsa_id": "GHSA-35q6-8fhf-pg65",
  "github_reviewed_at": null,
  "html_url": "https://github.com/advisories/GHSA-35q6-8fhf-pg65",
  "identifiers": [
    {
      "type": "GHSA",
      "value": "GHSA-35q6-8fhf-pg65"
    },
    {
      "type": "CVE",
      "value": "CVE-2026-97926"
    }
  ],
  "nvd_published_at": "2026-09-25T11:17:19Z",
  "published_at": "2026-09-25T12:31:28Z",
  "references": [
    "https://nvd.nist.gov/vuln/detail/CVE-2026-97926",
    "https://git.kernel.org/stable/c/5902a95066883cf96fa15b2680694fc5dd0c7d11",
    "https://git.kernel.org/stable/c/87b12dc360a002eb2d498aa4f01e84347019612d",
    "https://git.kernel.org/stable/c/abde9eb33106850dfa367ad3965d3588bb8558d5",
    "https://git.kernel.org/stable/c/c9d263be26806d388129fab8c6904bed197fc6af",
    "https://github.com/advisories/GHSA-35q6-8fhf-pg65"
  ],
  "repository_advisory_url": null,
  "severity": "high",
  "source_code_location": "",
  "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nufs: validate cylinder group...",
  "type": "unreviewed",
  "updated_at": "2026-09-25T15:31:44Z",
  "url": "https://api.github.com/advisories/GHSA-35q6-8fhf-pg65",
  "vulnerabilities": [],
  "withdrawn_at": null
}

{
  "credits": [],
  "cve_id": "CVE-2026-97926",
  "cvss": {
    "score": 7.0,
    "vector_string": "CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H"
  },
  "cvss_severities": {
    "cvss_v3": {
      "score": 7.0,
      "vector_string": "CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H"
    },
    "cvss_v4": {
      "score": 0.0,
      "vector_string": null
    }
  },
  "cwes": [],
  "description": "In the Linux kernel, the following vulnerability has been resolved:\n\nufs: validate cylinder group metadata before caching it\n\nufs_read_cylinder() copies the cylinder group index and the rotor\npositions straight from the on-disk group and caches them without any\ncheck:\n\n\tucpi->c_cgx    = fs32_to_cpu(sb, ucg->cg_cgx);\n\tucpi->c_rotor  = fs32_to_cpu(sb, ucg->cg_rotor);\n\tucpi->c_frotor = fs32_to_cpu(sb, ucg->cg_frotor);\n\tucpi->c_irotor = fs32_to_cpu(sb, ucg->cg_irotor);\n\nThey are then used as indices during allocation and free:\n\n  - c_cgx indexes the cylinder summary array as\n    UFS_SB(sb)->fs_cs(ucpi->c_cgx), so a value past s_ncg writes a 32\n    bit count outside the s_csp allocation.\n\n  - c_frotor becomes a bitmap scan start, start = c_frotor >> 3, and\n    then length = ((s_fpg + 7) >> 3) - start. A start beyond the block\n    bitmap wraps the unsigned length to a huge value, so ubh_scanc()\n    walks far past the cylinder group buffers. c_irotor drives the\n    inode bitmap the same way.\n\nA crafted image can set any of these freely, turning an ordinary\nallocation into an out of bounds access.\n\nReject a cylinder group whose recorded index does not match the group\nbeing read, or whose rotors fall outside the group, before the metadata\nis cached. Valid filesystems keep cg_cgx equal to the group number and\nthe rotors within the group, so only malformed images are rejected.",
  "epss": {
    "percentage": 0.00154,
    "percentile": 0.03802
  },
  "ghsa_id": "GHSA-35q6-8fhf-pg65",
  "github_reviewed_at": null,
  "html_url": "https://github.com/advisories/GHSA-35q6-8fhf-pg65",
  "identifiers": [
    {
      "type": "GHSA",
      "value": "GHSA-35q6-8fhf-pg65"
    },
    {
      "type": "CVE",
      "value": "CVE-2026-97926"
    }
  ],
  "nvd_published_at": "2026-09-25T11:17:19Z",
  "published_at": "2026-09-25T12:31:28Z",
  "references": [
    "https://nvd.nist.gov/vuln/detail/CVE-2026-97926",
    "https://git.kernel.org/stable/c/5902a95066883cf96fa15b2680694fc5dd0c7d11",
    "https://git.kernel.org/stable/c/87b12dc360a002eb2d498aa4f01e84347019612d",
    "https://git.kernel.org/stable/c/abde9eb33106850dfa367ad3965d3588bb8558d5",
    "https://git.kernel.org/stable/c/c9d263be26806d388129fab8c6904bed197fc6af",
    "https://github.com/advisories/GHSA-35q6-8fhf-pg65"
  ],
  "repository_advisory_url": null,
  "severity": "high",
  "source_code_location": "",
  "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nufs: validate cylinder group...",
  "type": "unreviewed",
  "updated_at": "2026-09-25T15:31:44Z",
  "url": "https://api.github.com/advisories/GHSA-35q6-8fhf-pg65",
  "vulnerabilities": [],
  "withdrawn_at": null
}