# CVE-2026-89999: HID: wacom: validate report length in wacom_intuos_pro2_bt_irq

> A malicious Bluetooth peripheral can trigger an out-of-bounds read in the Linux kernel Wacom driver, potentially leaking memory or causing a crash.

- **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:** Not needed
- **Fix available:** Yes
- **Published:** 16 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-101162, BELL-CVE-2026-89999, DEBIAN-CVE-2026-89999, GHSA-4g38-8hm5-638j, UBUNTU-CVE-2026-89999

## What is CVE-2026-89999?

CVE-2026-89999 is a high-severity memory corruption vulnerability in Linux, published on 16 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

HID: wacom: validate report length in wacom_intuos_pro2_bt_irq

wacom_intuos_pro2_bt_irq() receives the wire report length in `len`
but never consults it before parsing. After the report-id gate it
unconditionally calls wacom_intuos_pro2_bt_pen() and then, selected by
features.type, a fixed chain of sub-parsers, none of which receive
`len`:

	wacom_intuos_pro2_bt_pen(wacom);
	if (type == INTUOSP2_BT || type == INTUOSP2S_BT) {
		wacom_intuos_pro2_bt_touch(wacom);
		wacom_intuos_pro2_bt_pad(wacom);
		wacom_intuos_pro2_bt_battery(wacom);
	} else {
		wacom_intuos_gen3_bt_pad(wacom);
		wacom_intuos_gen3_bt_battery(wacom);
	}

Each sub-parser dereferences wacom->data at fixed offsets. The furthest
byte touched on each branch is:

  INTUOSP2_BT / INTUOSP2S_BT: wacom_intuos_pro2_bt_pad() reads data[285]
	(the touchring byte), so the report must be at least 286 bytes;
  INTUOSHT3_BT ("gen3"): wacom_intuos_gen3_bt_battery() reads data[45],
	so the report must be at least 46 bytes.

features.type is selected from the VID/PID id_table entry and
wacom_setup_device_quirks() force-registers the pen/pad/touch inputs
for that type independent of the report descriptor, so a malicious or
malfunctioning paired/spoofed Bluetooth peripheral can advertise that
VID/PID and send an undersized report that still satisfies the
data[0] == 0x80/0x81 gate. The driver then reads past the received
report and forwards the bytes to userspace via evdev (MSC_SERIAL /
ABS_MISC / ABS_WHEEL on the pen and pad input nodes), an out-of-bounds
read with a concrete userspace read-back channel, and a true
out-of-bounds read on transports whose backing buffer is sized to the
(small) report descriptor rather than a fixed-size staging buffer.

This is the same class of bug commit 2f1763f62909 ("HID: wacom: fix
out-of-bounds read in wacom_intuos_bt_irq") already hardened in the
sibling wacom_intuos_bt_irq(), which guards each report id against its
minimum length before parsing.

Guard wacom_intuos_pro2_bt_irq() the same way: before parsing, reject
reports shorter than the furthest offset the selected branch actually
dereferences, warn, and bail out. Because the whole pen/touch/pad/
battery chain runs unconditionally per branch, a single up-front check
against the maximum offset (286 bytes for INTUOSP2_BT/INTUOSP2S_BT,
46 bytes for the gen3 branch) bounds every sub-parser. Returning 0 on
a short report also skips those calls for the same malformed report,
which is the safe, conservative behavior.

## Which versions are affected by CVE-2026-89999?


## How do I fix CVE-2026-89999?

Apply the vendor's patch.

## Is CVE-2026-89999 being exploited?

There is no known exploitation of CVE-2026-89999 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-89999 and fix it if it is affected.

What it is: CVE-2026-89999 is a high-severity memory corruption vulnerability in Linux, published on 16 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-89999 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-2026-89999/ (Markdown: https://insights.sbomify.com/CVE-2026-89999/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-89999
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-89999
- OSV: https://osv.dev/vulnerability/CVE-2026-89999

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-89999/
Summaries are generated and may contain mistakes; the official description above is the record.