CVE-2026-64533

CVE-2026-64533: reported vulnerability affecting the affected product. Check CVSS, KEV status, business impact and recommended administrator actions.
CVE-2026-64533Linux

CVE-2026-64533

CVE-2026-64533: reported vulnerability affecting the affected product. Check CVSS, KEV status, business impact and recommended administrator actions.

CVSS
-
EPSS
-
Known exploited
not in KEV
Product
-

What is known

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]

Business impact

Successful exploitation of CVE-2026-64533, a reported vulnerability affecting the affected product, may affect the confidentiality, integrity or availability of the vulnerable environment. The exact impact depends on the installed version, exposed interfaces and deployment configuration.

Recommended administrator action

Confirm whether the affected product is present and compare installed versions with the vendor advisory and NVD record. Apply the vendor patch or documented mitigation; until remediation is complete, reduce exposure of affected interfaces, review relevant logs and monitor for indicators of exploitation. DataHouse can support version verification, managed patching, network exposure reduction, log review and backup validation for dedicated, cloud and colocated environments.

Sources

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