Vulnerability Database

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Total vulnerabilities in the database

CVE-2026-31716 — linux / linux_kernel

Out-of-bounds Write

In the Linux kernel, the following vulnerability has been resolved:

fs/ntfs3: validate rec->used in journal-replay file record check

check_file_record() validates rec->total against the record size but never validates rec->used. The do_action() journal-replay handlers read rec->used from disk and use it to compute memmove lengths:

DeleteAttribute: memmove(attr, ..., used - asize - roff) CreateAttribute: memmove(..., attr, used - roff) change_attr_size: memmove(..., used - PtrOffset(rec, next))

When rec->used is smaller than the offset of a validated attribute, or larger than the record size, these subtractions can underflow allowing us to copy huge amounts of memory in to a 4kb buffer, generally considered a bad idea overall.

This requires a corrupted filesystem, which isn't a threat model the kernel really needs to worry about, but checking for such an obvious out-of-bounds value is good to keep things robust, especially on journal replay

Fix this up by bounding rec->used correctly.

This is much like commit b2bc7c44ed17 ("fs/ntfs3: Fix slab-out-of-bounds read in DeleteIndexEntryRoot") which checked different values in this same switch statement.

  • Published: May 1, 2026
  • Updated: May 3, 2026
  • CVE: CVE-2026-31716
  • Severity: High
  • Exploit:
  • CISA KEV:

CVSS v3:

  • Severity: High
  • Score: 7.8
  • AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CWEs:

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