Linux Linux Kernel
CVE-2026-64432
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").
What this means for your business
- It affects Linux Kernel. It matters if your company, or a supplier that handles your data, runs it.
- An attacker can use it only with access to the machine itself, without a login, but only after tricking someone into an action such as opening a file or a link.
- FIRST's prediction model gives it a 0.2% chance of attack attempts being seen in the next 30 days, ranking above 7% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Linux Kernel, and which version. The affected versions are listed further down this page.
- 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.
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Scoring
- CVSS
- 7.8 (v3.1)
- Vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H- Weakness
- CWE-787
- Assigned by
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Dates
- Published
- 2026-07-25
- Last modified
- 2026-09-03
- Sources
- NVD
Affected products
- Linux Linux Kernel5.15 - 5.15.212, 5.16 - 6.1.178, 6.2 - 6.6.145, 6.7 - 6.12.96, 6.13 - 6.18.39, 6.19 - 7.1.4
As listed in the NVD configuration data. Not a statement about your estate.
References
- 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