# CVE-2026-46013: mm/memfd_luo: fix physical address conversion in put_folios cleanup

> Incorrect physical address conversion in Linux kernel memfd cleanup allows memory corruption, potentially leading to code execution or privilege escalation.

- **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:** 27 May 2026
- **Updated:** 14 Jun 2026
- **Also known as:** DEBIAN-CVE-2026-46013, GHSA-gxmw-vhgm-hqg8, UBUNTU-CVE-2026-46013

## What is CVE-2026-46013?

CVE-2026-46013 is a medium-severity memory corruption vulnerability in Linux kernel, published on 27 May 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/memfd_luo: fix physical address conversion in put_folios cleanup

In memfd_luo_retrieve_folios()'s put_folios cleanup path:

1. kho_restore_folio() expects a phys_addr_t (physical address) but
   receives a raw PFN (pfolio->pfn). This causes kho_restore_page() to
   check the wrong physical address (pfn << PAGE_SHIFT instead of the
   actual physical address).

2. This loop lacks the !pfolio->pfn check that exists in the main
   retrieval loop and memfd_luo_discard_folios(), which could
   incorrectly process sparse file holes where pfn=0.

Fix by converting PFN to physical address with PFN_PHYS() and adding
the !pfolio->pfn check, matching the pattern used elsewhere in this file.

This issue was identified by the AI review.
https://sashiko.dev/#/patchset/20260323110747.193569-1-duanchenghao@kylinos.cn

## Which versions are affected by CVE-2026-46013?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-46013?

Apply the vendor's patch.

## Is CVE-2026-46013 being exploited?

There is no known exploitation of CVE-2026-46013 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-2026-46013 and fix it if it is affected.

What it is: CVE-2026-46013 is a medium-severity memory corruption vulnerability in Linux kernel, published on 27 May 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-2026-46013 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-2026-46013/ (Markdown: https://insights.sbomify.com/CVE-2026-46013/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-46013
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-46013
- OSV: https://osv.dev/vulnerability/CVE-2026-46013

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-46013/
Summaries are generated and may contain mistakes; the official description above is the record.