FKIE_CVE-2026-80869

Vulnerability from fkie_nvd - Published: 2026-09-04 17:16 - Updated: 2026-09-04 17:16
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved: ntfs: bound the attribute-list entry in ntfs_read_inode_mount() The $MFT attribute-list walk in ntfs_read_inode_mount() validates each entry only with "(u8 *)al_entry + 6 > al_end" and "(u8 *)al_entry + le16_to_cpu(al_entry->length) > al_end", but then reads al_entry->lowest_vcn (an __le64 at offset 8) and al_entry->mft_reference (offset 16) -- fields beyond the 6 bytes proven in range. al_entry->length is attacker-controlled and only required non-zero, so a short entry (e.g. length 8) placed at the tail passes both checks while the lowest_vcn / mft_reference reads fall past al_end. al_end is ni->attr_list + attr_list_size (the on-disk size); the buffer is kvzalloc(round_up(attr_list_size, SECTOR_SIZE)), so the sector rounding usually absorbs the over-read -- but when attr_list_size is a multiple of SECTOR_SIZE there is no slack and a crafted $MFT attribute list produces an out-of-bounds read at mount time. Validate the entry with ntfs_attr_list_entry_is_valid() (added in patch 1/3) before dereferencing it, matching the bound the other attribute-list walks now use. The validator already requires the length to cover the fixed header, which makes the separate "!al_entry->length" check redundant, so drop it too.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/98634df5b1cb56c26299b7409227025ddb0167d8
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/c7a7e48e71ce915ec4cbd6e9f355590c1ecbc29a
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/ntfs/inode.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "c7a7e48e71ce915ec4cbd6e9f355590c1ecbc29a",
              "status": "affected",
              "version": "1e9ea7e04472d4e5e12e58c881eaacfb3e49b669",
              "versionType": "git"
            },
            {
              "lessThan": "98634df5b1cb56c26299b7409227025ddb0167d8",
              "status": "affected",
              "version": "1e9ea7e04472d4e5e12e58c881eaacfb3e49b669",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/ntfs/inode.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "7.1"
            },
            {
              "lessThan": "7.1",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nntfs: bound the attribute-list entry in ntfs_read_inode_mount()\n\nThe $MFT attribute-list walk in ntfs_read_inode_mount() validates each\nentry only with \"(u8 *)al_entry + 6 \u003e al_end\" and\n\"(u8 *)al_entry + le16_to_cpu(al_entry-\u003elength) \u003e al_end\", but then reads\nal_entry-\u003elowest_vcn (an __le64 at offset 8) and al_entry-\u003emft_reference\n(offset 16) -- fields beyond the 6 bytes proven in range. al_entry-\u003elength\nis attacker-controlled and only required non-zero, so a short entry (e.g.\nlength 8) placed at the tail passes both checks while the lowest_vcn /\nmft_reference reads fall past al_end.\n\nal_end is ni-\u003eattr_list + attr_list_size (the on-disk size); the buffer is\nkvzalloc(round_up(attr_list_size, SECTOR_SIZE)), so the sector rounding\nusually absorbs the over-read -- but when attr_list_size is a multiple of\nSECTOR_SIZE there is no slack and a crafted $MFT attribute list produces an\nout-of-bounds read at mount time.\n\nValidate the entry with ntfs_attr_list_entry_is_valid() (added in patch\n1/3) before dereferencing it, matching the bound the other attribute-list\nwalks now use. The validator already requires the length to cover the fixed\nheader, which makes the separate \"!al_entry-\u003elength\" check redundant, so\ndrop it too."
    }
  ],
  "id": "CVE-2026-80869",
  "lastModified": "2026-09-04T17:16:58.750",
  "metrics": {},
  "published": "2026-09-04T17:16:58.750",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/98634df5b1cb56c26299b7409227025ddb0167d8"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/c7a7e48e71ce915ec4cbd6e9f355590c1ecbc29a"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.