# CVE-2023-28642: AppArmor bypass with symlinked /proc in runc

> Attackers can bypass AppArmor security controls in runc containers by exploiting symlinked /proc mounts, requiring specific configurations.

- **Severity:** Medium 6.1 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L`)
- **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:** 29 Mar 2023
- **Updated:** 12 Feb 2025
- **Also known as:** AZL-25850, CLEANSTART-2026-HM12988, DEBIAN-CVE-2023-28642, GHSA-g2j6-57v7-gm8c, GO-2023-1683, OESA-2023-1217, OESA-2023-1218, OESA-2023-1383, UBUNTU-CVE-2023-28642

## What is CVE-2023-28642?

CVE-2023-28642 is a medium-severity vulnerability in opencontainers runc, published on 29 Mar 2023. 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

runc is a CLI tool for spawning and running containers according to the OCI specification. It was found that AppArmor can be bypassed when `/proc` inside the container is symlinked with a specific mount configuration. This issue has been fixed in runc version 1.1.5, by prohibiting symlinked `/proc`. See PR #3785 for details. users are advised to upgrade. Users unable to upgrade should avoid using an untrusted container image.

Weakness: CWE-59 (Improper Link Resolution Before File Access), CWE-281 (Improper Preservation of Permissions)

## Which versions are affected by CVE-2023-28642?

3 open source packages ship an affected version, including github.com/opencontainers/runc. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/opencontainers/runc` | Go | All versions | 1.1.5 |
| `github.com/opencontainers/runc` | Go | All versions | 1.1.5 |
| `github.com/opencontainers/runc` | Go | All versions | 1.1.5 |

Products: Linuxfoundation Runc.

## How do I fix CVE-2023-28642?

Upgrade github.com/opencontainers/runc to 1.1.5 or later.

## Is CVE-2023-28642 being exploited?

There is no known exploitation of CVE-2023-28642 in the wild and no public exploit code.

## Other vulnerabilities in opencontainers runc

- [CVE-2025-52565](https://insights.sbomify.com/CVE-2025-52565/): container escape due to /dev/console mount and related races (high 8.4)
- [CVE-2025-31133](https://insights.sbomify.com/CVE-2025-31133/): runc container escape via "masked path" abuse due to mount race conditions (high 7.3)
- [CVE-2025-52881](https://insights.sbomify.com/CVE-2025-52881/): runc: LSM labels can be bypassed with malicious config using dummy procfs files (high 7.3)
- [CVE-2023-25809](https://insights.sbomify.com/CVE-2023-25809/): rootless: `/sys/fs/cgroup` is writable when cgroupns isn't unshared in runc (medium 5.0)
- [CVE-2024-45310](https://insights.sbomify.com/CVE-2024-45310/): runc can be confused to create empty files/directories on the host (low 3.6)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-28642 and fix it if it is affected.

What it is: CVE-2023-28642 is a medium-severity vulnerability in opencontainers runc, published on 29 Mar 2023. 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-2023-28642 in the wild and no public exploit code.

Affected packages and fixed versions:
- github.com/opencontainers/runc (Go): affected all versions; fixed in 1.1.5
- github.com/opencontainers/runc (Go): affected all versions; fixed in 1.1.5
- github.com/opencontainers/runc (Go): affected all versions; fixed in 1.1.5

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-2023-28642/ (Markdown: https://insights.sbomify.com/CVE-2023-28642/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-28642
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-28642
- OSV: https://osv.dev/vulnerability/CVE-2023-28642

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-28642/
Summaries are generated and may contain mistakes; the official description above is the record.