CVE-2026-64533

Status: UPDATED  |  Advisory ID: CVE-2026-64533

Key Details

Affected Products, Subsystems & Sectors

What to Know

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

fs/ntfs3: validate lcns_follow in log_replay conversion

log_replay() converts DIR_PAGE_ENTRY_32 records into DIR_PAGE_ENTRY

records when replaying version 0 restart tables.

During this conversion, the memmove() length is derived directly from

the on-disk lcns_follow field:

memmove(&dp->vcn, &dp0->vcn_low,

2 * sizeof(u64) +

le32_to_cpu(dp->lcns_follow) * sizeof(u64));

check_rstbl() validates restart table structure, but does not constrain

per-entry lcns_follow values relative to the entry size. A malformed

filesystem image can provide an oversized lcns_follow value, causing

the conversion memmove() to access memory beyond the bounds of the

allocated restart table buffer.

The same field is later used to bound iteration over page_lcns[],

so validating lcns_follow during conversion also prevents downstream

out-of-bounds access from the same malformed metadata.

Compute the maximum valid lcns_follow from the already-validated

restart table entry size and reject entries that exceed this bound.

Reuse the existing t16/t32 scratch variables already declared in

log_replay() to avoid introducing new declarations.

[[email protected]: fixed the conflicts] (NVD)

What to Do

Monitor Linux's web page for any future patch releases.

References