# CVE-2026-31459: mm/damon/sysfs: fix param_ctx leak on damon_sysfs_new_test_ctx() failure

> A memory leak in the Linux kernel DAMON sysfs interface can lead to resource exhaustion and denial of service under specific failure conditions.

- **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:** 22 Apr 2026
- **Updated:** 23 May 2026
- **Also known as:** BELL-CVE-2026-31459, DEBIAN-CVE-2026-31459, GHSA-6c8g-q98p-w229, UBUNTU-CVE-2026-31459

## What is CVE-2026-31459?

CVE-2026-31459 is a medium-severity memory corruption vulnerability in Linux kernel, published on 22 Apr 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:

mm/damon/sysfs: fix param_ctx leak on damon_sysfs_new_test_ctx() failure

Patch series "mm/damon/sysfs: fix memory leak and NULL dereference
issues", v4.

DAMON_SYSFS can leak memory under allocation failure, and do NULL pointer
dereference when a privileged user make wrong sequences of control.  Fix
those.

This patch (of 3):

When damon_sysfs_new_test_ctx() fails in damon_sysfs_commit_input(),
param_ctx is leaked because the early return skips the cleanup at the out
label.  Destroy param_ctx before returning.

Weakness: CWE-401 (Missing Release of Memory after Effective Lifetime)

## Which versions are affected by CVE-2026-31459?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-31459?

Apply the vendor's patch.

## Is CVE-2026-31459 being exploited?

There is no known exploitation of CVE-2026-31459 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-2026-31459 and fix it if it is affected.

What it is: CVE-2026-31459 is a medium-severity memory corruption vulnerability in Linux kernel, published on 22 Apr 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-2026-31459 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-2026-31459/ (Markdown: https://insights.sbomify.com/CVE-2026-31459/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-31459
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-31459
- OSV: https://osv.dev/vulnerability/CVE-2026-31459

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-31459/
Summaries are generated and may contain mistakes; the official description above is the record.