CVEvulnerability
CVE-2026-98499
8.1 HIGH
Official page ↗
- Status
- Received
- Published
- 2026-10-18
- Last modified
- 2026-10-24
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- CVSS 3.1 (416baaa9-dc9f-4396-8d5f-8c081fb06d67)
- 8.1 HIGH — CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
Description
In the Linux kernel, the following vulnerability has been resolved:
HID: wacom: fix OOB read in wacom_wac_pen_serial_enforce()
The 'wacom_wac_pen_serial_enforce()' function may calculate and pass an
invalid offset to hid_field_extract(), resulting in memory reads at
incorrect addresses -- possibly beyond the end of the report. If a
field in the HID descriptor lists more usages than its Report Count
actually reserves space for, the function's inner 'j' will walk past
the end of the field:
for (i = 0; i < report->maxfield; i++) {
for (j = 0; j < report->field[i]->maxusage; j++) {
...
value = hid_field_extract(hdev, raw_data + 1,
offset + j * size, size);
A descriptor listing 12288 usages against Report Count 1 has the loop
extract the usage at index 12287 from bit offset 98296 -- about 12 KB
past a 2-byte received report. The value is stored in
wacom_wac->serial[0] and can reach userspace as an MSC_SERIAL event,
making this an information disclosure.
Clamp the loop to field->report_count, the number of value slots the
report holds. Value slots past the last declared usage are still
scanned; they reuse that usage (HID 1.11, 6.2.2.8).
Verified on v6.12.105 with a UHID reproducer: a 2-byte report from
such a descriptor trips KASAN before the patch and not after it.
References
- https://git.kernel.org/stable/c/26471d954bbfbfb9032994f7f485802ee20e0582 git.kernel.org
- https://git.kernel.org/stable/c/456afe4707e23cc114ad833197f63b52bb8fd1e7 git.kernel.org
- https://git.kernel.org/stable/c/4b09b7c84b8633cd041181616bd15bf5e73c164d git.kernel.org
- https://git.kernel.org/stable/c/65e7c4b5366b770c60dfefac3f1d06e33a9e411e git.kernel.org
- https://git.kernel.org/stable/c/9aa237cf66495b2426ddde8532e9b08a0ed83aaa git.kernel.org
- https://git.kernel.org/stable/c/9aa62f967b6a4bb30aa3b778e02c8a5ca6bcde51 git.kernel.org
- https://git.kernel.org/stable/c/c3129e6f26e18c0886ede7265f187a7ec289e1d1 git.kernel.org
- https://git.kernel.org/stable/c/eaa7d29341ef4b91e84ad097562982288a7c376c git.kernel.org