# 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.

- **Severity:** High 8.1 (`CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H`)
- **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:** Yes
- **Published:** 18 Oct 2026
- **Updated:** 24 Oct 2026
- **Also known as:** AZL-108768, BELL-CVE-2026-98499, DEBIAN-CVE-2026-98499, GHSA-vgmm-5fmr-gjgq, UBUNTU-CVE-2026-98499

## 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.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98499 and fix it if it is affected.

What it is: 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.
Exploitation: There is no known exploitation of CVE-2026-98499 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-98499/ (Markdown: https://insights.sbomify.com/CVE-2026-98499/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98499
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98499
- OSV: https://osv.dev/vulnerability/CVE-2026-98499

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98499/
Summaries are generated and may contain mistakes; the official description above is the record.