CVE-2026-80781
Received
Received - Intake
Out-of-Bounds Read in Linux Kernel HID Core
Vulnerability report for CVE-2026-80781, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-09-04
Last updated on: 2026-09-04
Assigner: kernel.org
Description
Description
In the Linux kernel, the following vulnerability has been resolved:
HID: core: fix OOB read of field->usage in hid_set_field()
hid_set_field() hands field->usage + offset to hid_dump_input() before
the guard that bounds offset:
hid_dump_input(field->report->device, field->usage + offset, value);
if (offset >= field->report_count) {
hid_err(...);
return -1;
}
Under CONFIG_DEBUG_FS hid_dump_input() dereferences that pointer, with
buf = hid_resolv_usage(usage->hid, NULL). The usage[] array is
allocated inline with the hid_field in hid_register_field() and holds
field->maxusage entries, so an offset past it reads off the end of the
kvzalloc()ed allocation and into a neighbouring object. Had the guard
run first, offset < report_count <= maxusage would already have confined
the pointer to the array.
A caller supplies such an offset today. picolcd_fb_send_tile()
validates only report->maxfield before issuing
hid_set_field(report->field[0], 11 + i, ...) for i = 0..31, so its
offsets are fixed at 11..42 and are never checked against the bound
field. When the device registers that field with fewer usages, the
framebuffer deferred-io work drives the read on every tile. KASAN
reports a 4-byte slab-out-of-bounds read in hid_dump_input() below
hid_set_field(), and the same boot logs "offset (1) exceeds
report_count (1)" from the guard that runs only afterwards.
Move the hid_dump_input() call below the guard. Because
field->maxusage >= field->report_count, the guard then establishes that
field->usage + offset lies inside the array before it is dereferenced,
for every caller and without changing behaviour on the valid path.
Discovered by XBOW, triaged by Baul Lee <baul.lee@xbow.com>
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | * |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |
