CVE-2026-64532High· 7.8▾ Twilight

fs/ntfs3: bound NTFS_DE view.data_off in UpdateRecordData{Root,Allocation}

In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: bound NTFS_DE view.data_off in UpdateRecordData{Root,Allocation} In do_action()'s UpdateRecordDataRoot (fslog.c:3489) and UpdateRecordDataAllocation (fslog.c…

▾ Twilight zone — High severity, or a signal on a lesser flaw

Depth score43/ 100 · Moderate

impact 42.9 · likelihood 0 · exploitation 0

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Proof of concept

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Published

Jul 27, 2026

Updated

Oct 19, 2026

CVSS

7.8

Vendor

Linux

Product

Linux

CWE

—

Depth score

43 · Moderate

EPSS

0.13% · p3

Platforms

—

Source

CVEORG

Vector

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CISA SSVC

decided 2026-10-16

Exploitation: none
Automatable: no
Technical impact: total

Stakeholder-Specific Vulnerability Categorization from CISA's ADP record at CVE.org: whether exploitation is observed, whether an attack can be automated, and how much of the system is at stake. The CVSS score shown above comes from the assigning CNA record, not NVD.

EPSS history

Exploit-prediction probability, daily snapshots since Oct 16.

0.1% → 0.1%

Timeline

Disclosure to exploitation, from the record and what we observed since indexing it.

4 events · 91 days

Jul 27, 2026Published
Disclosed via CVEORG
Oct 16, 2026EPSS first tracked
0.1%
Oct 19, 2026Record revised
Last analysed / modified upstream
Oct 26, 2026EPSS peak
0.1% → 0.1%

Linux #cve.org

Affected

Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < b20e5a709d8bd190d6e4645606763c7423e694c1
Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < d41b382068ca4e64e421f736cdd700095464b6ac
Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < 429d653ca641d38a78609b8f62e81a0a5c780a2d
Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < 315d3a9a48b49f889da3d858a9307e677cb9e1bd
Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < be306b8d9143a9c076c804a7ca025d69caf9c448
Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < 36feda687afebae24c472202694448738809c411
Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < 3e127829e57f5190f612412ece4541cb96d5ec7a
Linux 5.15

Full technical detail▾

Overview

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

fs/ntfs3: bound NTFS_DE view.data_off in UpdateRecordData{Root,Allocation}

In do_action()'s UpdateRecordDataRoot (fslog.c:3489) and UpdateRecordDataAllocation (fslog.c:3697) cases, the memmove destination is Add2Ptr(e, le16_to_cpu(e->view.data_off)), where e->view.data_off comes from an on-disk NTFS_DE inside an INDEX_ROOT or INDEX_BUFFER. Neither case validates view.data_off + dlen against e->size; the existing check_if_index_root / check_if_alloc_index helpers walk the entry chain and validate the entry's offset, but not its internal view fields.

The neighbouring read sites (e.g., fs/ntfs3/index.c when iterating view entries) check view.data_off + view.data_size <= e->size. Apply the same bound at the two memmove sites.

Reproduced under UML+KASAN on mainline 8d90b09e6741 via pr_warn-only probe instrumentation: with view.data_off forced to 0xFFFC, the memmove writes 32 bytes past the end of the NTFS_DE.

This is similar in shape to Pavitra Jha's 2026-05-02 patch "fs/ntfs3: prevent oob in case UpdateRecordDataRoot" ([email protected]) which proposes calling ntfs3_bad_de_range(); that helper does not exist in mainline. This patch uses inline checks.

Affected

Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < b20e5a709d8bd190d6e4645606763c7423e694c1
Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < d41b382068ca4e64e421f736cdd700095464b6ac
Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < 429d653ca641d38a78609b8f62e81a0a5c780a2d
Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < 315d3a9a48b49f889da3d858a9307e677cb9e1bd
Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < be306b8d9143a9c076c804a7ca025d69caf9c448
Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < 36feda687afebae24c472202694448738809c411
Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < 3e127829e57f5190f612412ece4541cb96d5ec7a
Linux 5.15

Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

References

Related vulnerabilities

Connected by shared product, vendor, weakness, or advisory.

#cve.org

fs/ntfs3: bound NTFS_DE view.data_off in UpdateRecordData{Root,Allocation}

▾ Twilight zone — High severity, or a signal on a lesser flaw

Depth score43/ 100 · Moderate

impact 42.9 · likelihood 0 · exploitation 0

Overview

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

fs/ntfs3: bound NTFS_DE view.data_off in UpdateRecordData{Root,Allocation}

The neighbouring read sites (e.g., fs/ntfs3/index.c when iterating view entries) check view.data_off + view.data_size <= e->size. Apply the same bound at the two memmove sites.

Reproduced under UML+KASAN on mainline 8d90b09e6741 via pr_warn-only probe instrumentation: with view.data_off forced to 0xFFFC, the memmove writes 32 bytes past the end of the NTFS_DE.

Affected

Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < b20e5a709d8bd190d6e4645606763c7423e694c1

Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < d41b382068ca4e64e421f736cdd700095464b6ac

Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < 429d653ca641d38a78609b8f62e81a0a5c780a2d

Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < 315d3a9a48b49f889da3d858a9307e677cb9e1bd

Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < be306b8d9143a9c076c804a7ca025d69caf9c448

Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < 36feda687afebae24c472202694448738809c411

Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < 3e127829e57f5190f612412ece4541cb96d5ec7a

Linux 5.15