# CVE-2026-80918: HID: core: fix number/pointer type confusion on long items

> A type confusion in the Linux kernel HID core allows local attackers to leak kernel pointer addresses via dmesg when connecting malicious HID devices.

- **Severity:** Not scored
- **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:** 9 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-99965, BELL-CVE-2026-80918, DEBIAN-CVE-2026-80918, GHSA-vppq-2m7c-f4xg, UBUNTU-CVE-2026-80918

## What is CVE-2026-80918?

CVE-2026-80918 is a vulnerability in Linux, published on 9 Sep 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: core: fix number/pointer type confusion on long items

When fetch_item() is called by hid_scan_report() on an item with
HID_ITEM_TAG_LONG, it stores a pointer to the item data in
item->data.longdata instead of storing a value directly in
item->data.{u8/u16/u32}.

When item_udata() or item_sdata() encounters such an item, it incorrectly
assumes that the item is in short format, and therefore returns the lower
part of a kernel pointer reinterpreted as a number.

When a HID device is connected whose descriptor contains a
HID_GLOBAL_ITEM_TAG_REPORT_SIZE encoded in long format with size=4, this
causes the lower half of a kernel pointer to be printed into dmesg as a
number, like this:

    hid (null): invalid report_size 107953555

To fix it, let item_udata() and item_sdata() verify that the item is in
short format.

Note that this bug only affects hid_scan_report(), while the main parsing
pass hid_parse_collections() will always bail out when encountering a long
item.

Sidenote: There are currently no users of data.longdata; maybe we should
just remove any parsing of long-format descriptors as a follow-up.

## Which versions are affected by CVE-2026-80918?


## How do I fix CVE-2026-80918?

Apply the vendor's patch.

## Is CVE-2026-80918 being exploited?

There is no known exploitation of CVE-2026-80918 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-80918 and fix it if it is affected.

What it is: CVE-2026-80918 is a vulnerability in Linux, published on 9 Sep 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-2026-80918 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-2026-80918/ (Markdown: https://insights.sbomify.com/CVE-2026-80918/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-80918
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-80918
- OSV: https://osv.dev/vulnerability/CVE-2026-80918

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-80918/
Summaries are generated and may contain mistakes; the official description above is the record.