HIGH
ntfs3 RunUnpack Overflow
CVE-2026-46062
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
KernelScan AI6.0MEDIUM
01Description
In the Linux kernel, the following vulnerability has been resolved: ntfs3: fix integer overflow in run_unpack() volume boundary check The volume boundary check `lcn + len > sbi->used.bitmap.nbits` uses raw addition which can wrap around for large lcn and len values, bypassing the validation. Use check_add_overflow() as is already done for the adjacent prev_lcn + dlcn and vcn64 + len checks added by commit 3ac37e100385 ("ntfs3: Fix integer overflow in run_unpack()"). Found by fuzzing with a source-patched harness (LibAFL + QEMU).
02KernelScan AI Analysis
Risk summary
An integer overflow in NTFS3 filesystem's run_unpack() function allows malicious filesystem images to bypass volume boundary checks. This can lead to out-of-bounds memory access and potential filesystem corruption or kernel crashes when mounting crafted NTFS volumes.
Vulnerability analysis
The vulnerability occurs in the NTFS3 filesystem's run_unpack() function where a volume boundary check uses raw integer addition (lcn + len) that can wrap around for large values, bypassing validation. The fix replaces this with check_add_overflow() to safely detect overflow conditions before performing the boundary check. This requires local access and typically root privileges to mount malicious NTFS filesystems, making it a local privilege-dependent attack.
03Fix Versions
| Branch | Fixed in | Patch commit |
|---|---|---|
| 5.15 | 5.15.209 | 424858f9a048 |
| 6.1 | 6.1.175 | e73cd5aed6b1 |
| 6.12 | 6.12.86 | 60dab3e2931f |
| 6.18 | 6.18.27 | f1af27cec07a |
| 6.6 | 6.6.140 | a954061b334e |
| 7.0 | 7.0.4 | 6175d09c23be |
| mainline | 7.1-rc1 | 984a415f0195 |