CVE-2026-64432

What it is

In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: validate Dirty Page Table capacity in log_replay copy_lcns In the analysis pass of $LogFile journal replay, log_replay() copies LCNs from each action log record into an existing Dirty Page Table (DPT) entry without bounding the destination index. A crafted NTFS image with DPT entry lcns_follow=1 and an action log record with lcns_follow=2 produces a kernel slab out-of-bounds write at mount time: BUG: KASAN: slab-out-of-bounds in log_replay+0x654c/0xdb60 Write of size 8 at addr ffff8880095e1040 by task mount Two attacker-controlled fields can drive j+i past the allocated page_lcns[] array: 1. dp->lcns_follow (capacity) can be smaller than lrh->lcns_follow. 2. lrh->target_vcn may be smaller than dp->vcn, making the u64 subtraction wrap to a huge size_t. Validate target VCN delta and per-record LCN count against the DPT entry capacity, bail via the existing out: cleanup label with -EINVAL. This mirrors the bounds-check pattern added in commit b2bc7c44ed17 ("fs/ntfs3: Fix slab-out-of-bounds read in DeleteIndexEntryRoot") and commit 0ca0485e4b2e ("fs/ntfs3: validate rec->used in journal-replay file record check").

At a glance

Exploitability

Can be exploited locally on the machine without logging in, but needs a user to act. High risk of data exposure, data tampering, service disruption.

Exploit odds

0.1% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-07-25 10:17 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-10-19 21:17 UTC Last updatedMost recent change to the record

Details

Published

2026-07-25 10:17 UTC

Last modified

2026-10-19 21:17 UTC

Exploit probability

0.1% · EPSS, next 30 days

Weakness

CWE-787 · Out-of-bounds write

Record status

Modified

Affected

• Linux Kernel < 5.15.212
• Linux Kernel < 6.1.178
• Linux Kernel < 6.6.145
• Linux Kernel < 6.12.96
• Linux Kernel < 6.18.39
• Linux Kernel < 7.1.4

Attack profile CVSS 3.1 · 7.8

Attack vector

Local

Complexity

Low

Privileges needed

None

User interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High