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CVE-2026-90118

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: ntfs: fix off-by-one page overflow in ntfs_decompress() The per-token range check in ntfs_decompress() uses if (cb >= cb_sb_end || dp_addr > dp_sb_end) break; so dp_addr == dp_sb_end falls through to the symbol copy `*dp_addr++ = *cb++`, writing one byte past the destination page. Since NTFS_SB_SIZE == PAGE_SIZE the destination is a single page, so the byte lands in the adjacent page, and *dest_ofs is left one past the sub-block end (the later `*dest_ofs &= ~PAGE_MASK` then yields 1, not 0, so the page is never finalized and later sub-blocks keep writing further past it). A corrupted compressed $DATA attribute thus produces a bounded run of out-of-bounds writes when the file is read. Break as soon as dp_addr reaches dp_sb_end; a full sub-block still completes, as its final copy advances dp_addr to exactly dp_sb_end.

Severity
HIGH
CVSS score
7.8 (v3.1)
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-17 17:17:03.963000
Last modified
2026-10-19 09:19:01.290000
View original CVE JSON
{
  "id": "CVE-2026-90118",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-17T17:17:03.963",
  "lastModified": "2026-10-19T09:19:01.290",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nntfs: fix off-by-one page overflow in ntfs_decompress()\n\nThe per-token range check in ntfs_decompress() uses\n\n\tif (cb >= cb_sb_end || dp_addr > dp_sb_end)\n\t\tbreak;\n\nso dp_addr == dp_sb_end falls through to the symbol copy\n`*dp_addr++ = *cb++`, writing one byte past the destination page.  Since\nNTFS_SB_SIZE == PAGE_SIZE the destination is a single page, so the byte\nlands in the adjacent page, and *dest_ofs is left one past the sub-block\nend (the later `*dest_ofs &= ~PAGE_MASK` then yields 1, not 0, so the page\nis never finalized and later sub-blocks keep writing further past it).  A\ncorrupted compressed $DATA attribute thus produces a bounded run of\nout-of-bounds writes when the file is read.\n\nBreak as soon as dp_addr reaches dp_sb_end; a full sub-block still\ncompletes, as its final copy advances dp_addr to exactly dp_sb_end."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "fs/ntfs/compress.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "1e9ea7e04472d4e5e12e58c881eaacfb3e49b669",
              "lessThan": "b42644e425fed4a5cd6c88372655da5c1b52c666",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1e9ea7e04472d4e5e12e58c881eaacfb3e49b669",
              "lessThan": "98716c9fce21f6c8a9d71e08cf53e7504fa562f4",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "fs/ntfs/compress.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "7.1",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "7.1",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.6",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "REQUIRED",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/98716c9fce21f6c8a9d71e08cf53e7504fa562f4",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b42644e425fed4a5cd6c88372655da5c1b52c666",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}