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.
[almaz.alexandrovich@paragon-software.com: fixed the conflicts]
References
Configurations
No configuration.
History
30 Jul 2026, 06:25
| Type | Values Removed | Values Added |
|---|---|---|
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 7.8 |
27 Jul 2026, 08:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-07-27 08:16
Updated : 2026-07-30 06:25
NVD link : CVE-2026-64533
Mitre link : CVE-2026-64533
CVE.ORG link : CVE-2026-64533
JSON object : View
Products Affected
No product.
CWE
No CWE.