Out-of-bounds write in Linux kernel - CVE-2026-64432

Vulnerability identifier: #VU139511

CSH Severity: Low

CVSS v4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-64432

CWE-ID: CWE-787

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to cause a denial of service or execute arbitrary code.

The vulnerability exists due to an out-of-bounds write in log_replay in fs/ntfs3/fslog.c when mounting a crafted NTFS image and replaying the $LogFile journal. A local user can provide a specially crafted NTFS image to cause a denial of service or execute arbitrary code.

The issue can be triggered at mount time during the analysis pass when LCNs from an action log record are copied into an existing Dirty Page Table entry, and integer underflow in the target VCN delta can drive the destination index past the allocated page_lcns array.

Linux kernel
openEuler
Ubuntu
bpftool
python3-perf-debuginfo
python3-perf
perf-debuginfo
perf
kernel-tools-devel
kernel-tools-debuginfo
kernel-tools
kernel-source
kernel-headers
kernel-devel
kernel-debugsource
kernel-debuginfo
bpftool-debuginfo
kernel
linux (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
bpftool - update to 5.10.0-328.0.0.229
python3-perf-debuginfo - update to 5.10.0-328.0.0.229
python3-perf - update to 5.10.0-328.0.0.229
perf-debuginfo - update to 5.10.0-328.0.0.229
perf - update to 5.10.0-328.0.0.229
kernel-tools-devel - update to 5.10.0-328.0.0.229
kernel-tools-debuginfo - update to 5.10.0-328.0.0.229
kernel-tools - update to 5.10.0-328.0.0.229
kernel-source - update to 5.10.0-328.0.0.229
kernel-headers - update to 5.10.0-328.0.0.229
kernel-devel - update to 5.10.0-328.0.0.229
kernel-debugsource - update to 5.10.0-328.0.0.229
kernel-debuginfo - update to 5.10.0-328.0.0.229
bpftool-debuginfo - update to 5.10.0-328.0.0.229
kernel - update to 5.10.0-328.0.0.229
linux (Ubuntu package) - addressed in versions 7.0.0-31.31, 7.0.0-31.31.1, 7.0.0-31.31~24.04.1, 7.0.0-1006.7, 7.0.0-1011.11~24.04.1, 7.0.0-1012.12, 7.0.0-1012.12~24.04.1
linux-gcp-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1013.13

• https://git.kernel.org/stable/c/3aa96956ca2200674e2a8f9c23ec6ecd45e5010f
• https://git.kernel.org/stable/c/57382ec6ac63b63dce2789e835fded28b698ae79
• https://git.kernel.org/stable/c/946046841013ebac8492ef49651c53638d7a9a6a
• https://git.kernel.org/stable/c/964c3fae1dfc49dde5468eace940f199cda234e9
• https://git.kernel.org/stable/c/c6f9e804f73ef809529865fbc7256dd189ff8c33
• https://git.kernel.org/stable/c/cf28fc1658463d768657cf1c27a83980d4ba7ef2
• https://git.kernel.org/stable/c/f433acc85b86f327d03ba8b03a33c105c51053de

• Out-of-bounds write in Linux kernel ntfs3
• openEuler 22.03 LTS SP4 update for kernel
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux
• Ubuntu update for linux-gcp-7.0