# CVE-2026-80569: Input: synaptics-rmi4 - bound the F54 report size to the allocated buffer

> A malicious RMI4 device can trigger a buffer overflow in the Synaptics RMI4 driver, potentially leading to code execution or system crash.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 26 Aug 2026
- **Updated:** 27 Aug 2026
- **Also known as:** AZL-97803, BELL-CVE-2026-80569, DEBIAN-CVE-2026-80569, GHSA-3268-6g62-7794, UBUNTU-CVE-2026-80569

## What is CVE-2026-80569?

CVE-2026-80569 is a high-severity memory corruption vulnerability in Linux, published on 26 Aug 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:

Input: synaptics-rmi4 - bound the F54 report size to the allocated buffer

rmi_f54_work() reads a diagnostics report from the device into
f54->report_data, sizing the transfer with rmi_f54_get_report_size():

	report_size = rmi_f54_get_report_size(f54);
	...
	for (i = 0; i < report_size; i += F54_REPORT_DATA_SIZE) {
		int size = min(F54_REPORT_DATA_SIZE, report_size - i);
		...
		rmi_read_block(.., f54->report_data + i, size);
	}

report_data is allocated once at probe from F54's own electrode counts
(array3_size(f54->num_tx_electrodes, f54->num_rx_electrodes, sizeof(u16))),
but rmi_f54_get_report_size() computes the size from
drv_data->num_*_electrodes when those are set, i.e. from the F55
function's electrode counts. Both counts come straight from device
queries (F54 and F55 each report up to 255 electrodes) and nothing
constrains the F55 counts to the F54 ones.

A malicious or malfunctioning RMI4 device that reports larger F55
electrode counts than its F54 counts makes report_size exceed the
allocation, so the read loop writes past report_data (and the V4L2
dequeue memcpy() then reads past it). On conforming hardware the F55
configured electrodes are a subset of the F54 physical electrodes, so
report_size never exceeds the buffer and well-behaved devices are
unaffected.

Record the allocation size and reject a report that does not fit,
mirroring the existing zero-size check.

## Which versions are affected by CVE-2026-80569?


## How do I fix CVE-2026-80569?

Apply the vendor's patch.

## Is CVE-2026-80569 being exploited?

There is no known exploitation of CVE-2026-80569 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-80569 and fix it if it is affected.

What it is: CVE-2026-80569 is a high-severity memory corruption vulnerability in Linux, published on 26 Aug 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-2026-80569 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-2026-80569/ (Markdown: https://insights.sbomify.com/CVE-2026-80569/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-80569
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-80569
- OSV: https://osv.dev/vulnerability/CVE-2026-80569

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-80569/
Summaries are generated and may contain mistakes; the official description above is the record.