GHSA-vp62-88p7-qqf5
MEDIUMGHSA-vp62-88p7-qqf5 is a medium-severity (CVSS 6.1) CWE-81 vulnerability in github.com/docker/docker. O3 Security confirms whether GHSA-vp62-88p7-qqf5 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Docker: Race condition in docker cp allows creation of arbitrary empty files on the host via symlink swap
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 GHSA-vp62-88p7-qqf5.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-vp62-88p7-qqf5 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 360,142 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
github.com/docker/docker🐹github.com/moby/moby/v2🐹github.com/moby/mobyReal-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
Summary
A race condition during docker cp mount setup allows a malicious container to create empty files or directories at arbitrary absolute paths on the host filesystem.
This advisory covers the race during mountpoint creation. The related race during the subsequent mount syscall is tracked in GHSA-rg2x-37c3-w2rh
Details
When copying files into a container, the daemon sets up a temporary filesystem view by bind-mounting volumes into a private mount namespace. During this setup, the mount destination path is first resolved within the container's root filesystem using GetResourcePath, and then used to create the mountpoint (file or directory) if it does not already exist via createIfNotExists.
Between path resolution and mountpoint creation, a process running inside the container can swap a path component for a symlink pointing to an arbitrary location on the host. Because createIfNotExists operates on the already-resolved absolute path using standard os.MkdirAll and os.OpenFile — which follow symlinks in intermediate path components — the symlink is followed and the file or directory is created outside the container root filesystem, as root.
Impact
A malicious container can create empty files or directories at arbitrary absolute paths on the host filesystem, running as root. This enables persistent denial of service — for example:
- Converting
/etc/docker/daemon.jsoninto a directory prevents the daemon from restarting - Creating
/etc/nologinprevents user logins - Overwriting critical system paths with empty files can break host services
The container does not gain read or write access to existing host files — only the ability to create new empty files or directories at chosen paths.
Conditions for exploitation
- A container must be running with a process that can rapidly create and swap symlinks at a volume mount destination path.
- An operator must initiate a
docker cpinto that container, or call thePUT /containers/{id}/archiveorHEAD /containers/{id}/archiveAPI endpoints.
Not affected
- Containers that do not have volume mounts are not affected, as the race occurs during volume bind-mount setup.
Patches
Mountpoint creation is now scoped to the container root using os.Root (Go 1.24+), which refuses to follow symlinks that escape the opened root directory. All filesystem operations in createIfNotExists (MkdirAll, OpenFile) are performed through the os.Root handle, so even if a symlink swap occurs after path resolution, the creation stays confined to the container root.
Workarounds
- Only run containers from trusted images.
- Avoid using
docker cpwith untrusted running containers. - Use authorization plugins to restrict access to the archive API endpoints (
PUT /containers/{id}/archive,HEAD /containers/{id}/archive).
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/docker/docker | all versions | No fix |
| 🐹Go | github.com/moby/moby/v2 | all versions | 2.0.0-beta.14 |
| 🐹Go | github.com/moby/moby | all versions | No fix |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/docker/docker. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
No patched version of github.com/docker/docker has shipped for GHSA-vp62-88p7-qqf5 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
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.
How O3 protects you
O3 pinpoints whether GHSA-vp62-88p7-qqf5 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-vp62-88p7-qqf5. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
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.
This flaw is rated as Low impact. A race condition in the `docker cp` mount setup within the Moby container framework allows a malicious container to create empty files or directories at arbitrary locations on the host filesystem. Successful exploitation is difficult (AC:H) due to the timing-dependent nature of the…
Frequently Asked Questions
Is GHSA-vp62-88p7-qqf5 in your dependencies?
O3 detects GHSA-vp62-88p7-qqf5 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.