# CVE-2026-64273: Input: iforce - bound the device-reported force-feedback effect index

> A malicious USB or serial device can trigger an out-of-bounds write in the Linux kernel iforce driver, potentially leading to code execution or privilege escalation.

- **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:** 25 Jul 2026
- **Updated:** 17 Aug 2026
- **Also known as:** BELL-CVE-2026-64273, DEBIAN-CVE-2026-64273, GHSA-mwj6-9jph-6qp6, ROOT-OS-UBUNTU-2204-CVE-2026-64273, UBUNTU-CVE-2026-64273

## What is CVE-2026-64273?

CVE-2026-64273 is a high-severity memory corruption vulnerability in Linux kernel, published on 25 Jul 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: iforce - bound the device-reported force-feedback effect index

iforce_process_packet() handles a status report (packet id 0x02) by
taking a force-feedback effect index straight from the device wire and
using it to address the per-effect state array:

	i = data[1] & 0x7f;
	if (data[1] & 0x80) {
		if (!test_and_set_bit(FF_CORE_IS_PLAYED,
				      iforce->core_effects[i].flags))
			...
	} else if (test_and_clear_bit(FF_CORE_IS_PLAYED,
				      iforce->core_effects[i].flags)) {
		...
	}

The index is masked only with 0x7f, so it ranges 0..127, but
core_effects[] holds only IFORCE_EFFECTS_MAX (32) entries.  For an index
of 32..127 the test_and_set_bit()/test_and_clear_bit() is an
out-of-bounds single-bit read-modify-write past the array.  core_effects[]
is the second-to-last member of struct iforce, so the write lands in the
trailing members and beyond the embedding kzalloc()'d iforce_serio /
iforce_usb object.

data[1] is unvalidated device payload on both transports (the USB
interrupt endpoint and serio), and the status path is not gated on force
feedback being present, so a malicious or counterfeit device can set or
clear a bit at an attacker-chosen offset past the object.

Reject an out-of-range index instead of indexing with it.  Bound against
the array dimension IFORCE_EFFECTS_MAX rather than dev->ff->max_effects so
the check guarantees memory safety regardless of how many effects the
device registered.  A legitimate "effect started/stopped" status always
carries an index below IFORCE_EFFECTS_MAX, so well-formed devices are
unaffected; the neighbouring mark_core_as_ready() loop is already bounded
and is left untouched.

Weakness: CWE-129 (Improper Validation of Array Index)

## Which versions are affected by CVE-2026-64273?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-64273?

Apply the vendor's patch.

## Is CVE-2026-64273 being exploited?

There is no known exploitation of CVE-2026-64273 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-64273 and fix it if it is affected.

What it is: CVE-2026-64273 is a high-severity memory corruption vulnerability in Linux kernel, published on 25 Jul 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-2026-64273 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2026-64273/ (Markdown: https://insights.sbomify.com/CVE-2026-64273/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-64273
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-64273
- OSV: https://osv.dev/vulnerability/CVE-2026-64273

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-64273/
Summaries are generated and may contain mistakes; the official description above is the record.
