CVE-2026-98499 HID: wacom: fix OOB read in wacom_wac_pen_serial_enforce()
A malicious HID device can trigger an out-of-bounds read in the Wacom driver, leaking kernel memory to userspace via serial events.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-98499?
CVE-2026-98499 is a high-severity vulnerability in Linux, published on 18 Oct 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official 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.
Which versions are affected by CVE-2026-98499?
How do I fix CVE-2026-98499?
Apply the vendor's patch.
Is CVE-2026-98499 being exploited?
There is no known exploitation of CVE-2026-98499 in the wild and no public exploit code.
Sources
Also known as AZL-108768, BELL-CVE-2026-98499, DEBIAN-CVE-2026-98499, GHSA-vgmm-5fmr-gjgq, UBUNTU-CVE-2026-98499.