CVE-2023-28642 is a medium-severity (CVSS 6.1) CWE-281 vulnerability in github.com/opencontainers/runc. A fix is available for github.com/opencontainers/runc — see the affected versions and patch details below.
AppArmor bypass with symlinked /proc in runc
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2023-28642.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
github.com/opencontainers/runcReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/opencontainers/runc | all versions | 1.1.5go get github.com/opencontainers/runc@v1.1.5 |
Affected Products
runclinuxfoundationDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/opencontainers/runc, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/opencontainers/runc to 1.1.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-28642 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
The symlink vulnerability in runc allowing for the bypassing of AppArmor protections by manipulating the /proc symlink poses a moderate severity issue due to its potential impact on container isolation and security boundaries. While the exploitation requires specific mount configurations and access to the container's…
Avoid using an untrusted container image.Source: Red Hat security advisory for CVE-2023-28642 (CC BY 4.0)
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Enterprise Linux 8 | container-tools:4.0-8090020230828093056.e7857ab1 | RHSA-2023:6938 |
| Red Hat Enterprise Linux 8 | container-tools:rhel8-8090020230825121312.e7857ab1 | RHSA-2023:6939 |
| Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support | container-tools:3.0-8040020240104111259.c0c392d5 | RHSA-2024:0564 |
| Red Hat Enterprise Linux 9 | runc-4:1.1.9-1.el9 | RHSA-2023:6380 |
| Red Hat OpenShift Container Platform 4.13 | openshift4/ose-vsphere-csi-driver-syncer-rhel8:v4.13.0-202304190216.p0.g6f4295b.assembly.stream | RHSA-2023:1326 |
Frequently Asked Questions
Is CVE-2023-28642 in your dependencies?
Find it across Go, including transitive dependencies.