Linux Linux Kernel
CVE-2026-64361
In the Linux kernel, the following vulnerability has been resolved: hfs/hfsplus: fix u32 overflow in check_and_correct_requested_length check_and_correct_requested_length() compares (off + len) against node_size using u32 arithmetic. When the caller passes a large len value (e.g. from an underflowed subtraction in hfs_brec_remove()), off + len can wrap past 2^32 and produce a small result, causing the bounds check to pass when it should fail. For example, with off=14 and len=0xFFFFFFF2 (underflowed from data_off - keyoffset - size in hfs_brec_remove), off + len wraps to 6, which is less than a typical node_size of 512, so the check passes and the subsequent memmove reads ~4GB past the node buffer. Fix this by widening the addition to u64 before comparing against node_size. This prevents the u32 wrap while keeping the logic straightforward.
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, with an ordinary user login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.1% chance of attack attempts being seen in the next 30 days, ranking above 2% 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:L/UI:N/S:U/C:H/I:H/A:H- Weakness
- CWE-191
- Assigned by
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Dates
- Published
- 2026-07-25
- Last modified
- 2026-09-04
- Sources
- NVD
Affected products
- Linux Linux Kernel5.4.297 - 5.5, 5.10.241 - 5.10.261, 5.15.190 - 5.15.212, 6.1.149 - 6.1.178, 6.6.103 - 6.6.145, 6.12.43 - 6.12.97, 6.15.11 - 6.16, 6.16.2 - 6.18.40, 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/607217f7ad419b53926f71e3f75001813bbc08ad
- https://git.kernel.org/stable/c/671c3fcc2ad31c1311ea6414382a2d95104ae1b9
- https://git.kernel.org/stable/c/7399c3baee7bb622a92f0b895cd4d3009a693f2b
- https://git.kernel.org/stable/c/966cb76fb2857a4242cab6ea2ea17acf818a3da7
- https://git.kernel.org/stable/c/b6a481642ea1977be2f84dc08c5affd742c177e7
- https://git.kernel.org/stable/c/c25d3c931a63e762fcaa9cb125b901c53b62403f
- https://git.kernel.org/stable/c/c8dd112173c02adf539fe2ad34a45f5e0068780d
- https://git.kernel.org/stable/c/fc9d1447ca3cdc78d2e4ace1ce1f3a7c77ca08b1