# CVE-2026-46054: selinux: fix overlayfs mmap() and mprotect() access checks

> Attackers can bypass SELinux access controls on overlayfs files via mmap and mprotect, potentially accessing restricted data.

- **Severity:** High 7.1 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N`)
- **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:** 19 Oct 2026
- **Also known as:** ALSA-2026:27811, ALSA-2026:27812, AZL-88715, BELL-CVE-2026-46054, DEBIAN-CVE-2026-46054, GHSA-xg2q-7399-f2r3, RHSA-2026:27811, RHSA-2026:27812, RLSA-2026:27811, RLSA-2026:27812, ROOT-OS-DEBIAN-11-CVE-2026-46054, ROOT-OS-DEBIAN-12-CVE-2026-46054, ROOT-OS-DEBIAN-13-CVE-2026-46054, ROOT-OS-UBUNTU-2204-CVE-2026-46054, ROOT-OS-UBUNTU-2404-CVE-2026-46054, UBUNTU-CVE-2026-46054

## What is CVE-2026-46054?

CVE-2026-46054 is a high-severity missing authorization 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:

selinux: fix overlayfs mmap() and mprotect() access checks

The existing SELinux security model for overlayfs is to allow access if
the current task is able to access the top level file (the "user" file)
and the mounter's credentials are sufficient to access the lower
level file (the "backing" file).  Unfortunately, the current code does
not properly enforce these access controls for both mmap() and mprotect()
operations on overlayfs filesystems.

This patch makes use of the newly created security_mmap_backing_file()
LSM hook to provide the missing backing file enforcement for mmap()
operations, and leverages the backing file API and new LSM blob to
provide the necessary information to properly enforce the mprotect()
access controls.

Weakness: CWE-280 (Improper Handling of Insufficient Permissions or Privileges), CWE-862 (Missing Authorization)

## Which versions are affected by CVE-2026-46054?

It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `bpftool` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `kernel` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `kernel-abi-stablelists` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `kernel-core` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `kernel-cross-headers` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `kernel-debug` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `kernel-debug-core` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `kernel-debug-devel` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `kernel-debug-modules` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `kernel-debug-modules-extra` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `kernel-devel` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `kernel-doc` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `kernel-headers` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `kernel-modules` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `kernel-modules-extra` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `kernel-rt` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.rt7.478.el8_10 |
| `kernel-rt-core` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.rt7.478.el8_10 |
| `kernel-rt-debug` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.rt7.478.el8_10 |
| `kernel-rt-debug-core` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.rt7.478.el8_10 |
| `kernel-rt-debug-devel` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.rt7.478.el8_10 |
| `kernel-rt-debug-modules` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.rt7.478.el8_10 |
| `kernel-rt-debug-modules-extra` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.rt7.478.el8_10 |
| `kernel-rt-devel` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.rt7.478.el8_10 |
| `kernel-rt-modules` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.rt7.478.el8_10 |
| `kernel-rt-modules-extra` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.rt7.478.el8_10 |
| `kernel-tools` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `kernel-tools-libs` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `kernel-tools-libs-devel` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `kernel-zfcpdump` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `kernel-zfcpdump-core` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `kernel-zfcpdump-devel` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `kernel-zfcpdump-modules` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `kernel-zfcpdump-modules-extra` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `perf` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `python3-perf` | AlmaLinux:8 | All versions | 4.18.0-553.137.1.el8_10 |
| `bpftool` | Red Hat:enterprise_linux:8::baseos | All versions | 0:4.18.0-553.137.1.el8_10 |
| `bpftool-debuginfo` | Red Hat:enterprise_linux:8::baseos | All versions | 0:4.18.0-553.137.1.el8_10 |
| `kernel` | Red Hat:enterprise_linux:8::baseos | All versions | 0:4.18.0-553.137.1.el8_10 |
| `kernel-abi-stablelists` | Red Hat:enterprise_linux:8::baseos | All versions | 0:4.18.0-553.137.1.el8_10 |
| `kernel-core` | Red Hat:enterprise_linux:8::baseos | All versions | 0:4.18.0-553.137.1.el8_10 |

Products: Linux kernel.

## How do I fix CVE-2026-46054?

Apply the vendor's patch.

## Is CVE-2026-46054 being exploited?

There is no known exploitation of CVE-2026-46054 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-2026-46054 and fix it if it is affected.

What it is: CVE-2026-46054 is a high-severity missing authorization 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-2026-46054 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-2026-46054/ (Markdown: https://insights.sbomify.com/CVE-2026-46054/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-46054
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-46054
- OSV: https://osv.dev/vulnerability/CVE-2026-46054

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-46054/
Summaries are generated and may contain mistakes; the official description above is the record.