# CVE-2026-46315: io_uring/waitid: clear waitid info before copying it to userspace

> A local attacker can read uninitialized kernel memory via the io_uring waitid operation, potentially exposing sensitive data.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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:** 9 Jun 2026
- **Updated:** 14 Jun 2026
- **Also known as:** BELL-CVE-2026-46315, DEBIAN-CVE-2026-46315, GHSA-3xr6-r26v-fpqm, ROOT-OS-DEBIAN-13-CVE-2026-46315, ROOT-OS-UBUNTU-2404-CVE-2026-46315, UBUNTU-CVE-2026-46315

## What is CVE-2026-46315?

CVE-2026-46315 is a medium-severity vulnerability in Linux kernel, published on 9 Jun 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:

io_uring/waitid: clear waitid info before copying it to userspace

IORING_OP_WAITID stores its result fields in struct io_waitid::info and
later copies them to userspace siginfo. The prep path initializes the
request arguments, but it does not initialize info itself.

If the wait operation completes without reporting a child event, the common
wait code can return without writing wo_info. In that case io_waitid_finish()
still copies iw->info to userspace, exposing stale bytes from the reused
io_kiocb command storage.

Clear the result storage during prep so the io_uring path matches the
regular waitid syscall, which uses a zero-initialized struct waitid_info.

## Which versions are affected by CVE-2026-46315?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-46315?

Apply the vendor's patch.

## Is CVE-2026-46315 being exploited?

There is no known exploitation of CVE-2026-46315 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-2026-46315 and fix it if it is affected.

What it is: CVE-2026-46315 is a medium-severity vulnerability in Linux kernel, published on 9 Jun 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-2026-46315 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-2026-46315/ (Markdown: https://insights.sbomify.com/CVE-2026-46315/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-46315
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-46315
- OSV: https://osv.dev/vulnerability/CVE-2026-46315

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-46315/
Summaries are generated and may contain mistakes; the official description above is the record.