medium CVSS 6.8

CVE-2026-33997·Docker vulnerability

Moby is an open source container framework. Prior to version 29.3.1, a security vulnerability has been detected that allows plugins privilege validation to be bypassed during docker plugin install. Due to an error in the daemon's privilege comparison logic, the daemon may incorrectly accept a privilege set that differs from the one approved by the user. Plugins that request exactly one privilege are also affected, because no comparison is performed at all. This issue has been patched in version 29.3.1.

Severity
medium
Software
Docker
Fixed in
29.3.1
Published
2026-03-31

Affected versions

Until: 29.3.1

Fixed in: 29.3.1

How to fix this CVE

Update Docker to version 29.3.1 or later to address a plugin privilege validation bypass that could allow unauthorized permission escalation during plugin installation. The vulnerability stems from flawed privilege comparison logic in the Docker daemon that may accept unapproved privilege sets. Immediate patching is recommended for any Docker deployment running versions prior to 29.3.1.

sudo dnf update docker-ce

Defensia detects this vulnerability

How to check if you are affected

  1. Run 'docker --version' to check your installed Docker version and confirm if it is below 29.3.1
  2. Execute 'docker plugin list' to enumerate all installed plugins and their requested permissions
  3. Review Docker daemon logs with 'sudo journalctl -u docker -n 1000' to search for plugin installation events and any permission-related warnings
  4. After upgrading, re-run 'docker --version' and verify the output shows version 29.3.1 or later

FAQ

What is CVE-2026-33997?

This vulnerability affects Docker's plugin installation mechanism, where the daemon's privilege validation logic fails to properly enforce user-approved permissions. Attackers exploiting this flaw could install plugins with elevated privileges beyond what was explicitly authorized.

Is CVE-2026-33997 being actively exploited?

No, this vulnerability is not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog and no public exploits are available. However, the medium severity rating and ease of exploitation warrant timely patching.

What versions of Docker are affected by CVE-2026-33997?

All Docker versions prior to 29.3.1 are affected. The vulnerability impacts the Moby open source container framework underlying Docker, affecting both standalone plugins and those requesting single privileges.

How do I check if my server is vulnerable to CVE-2026-33997?

Run 'docker --version' and compare the version number to 29.3.1. Any version below 29.3.1 is vulnerable. Additionally, check 'docker plugin list' to see if any plugins are currently installed on the system.

Does Defensia detect CVE-2026-33997?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Docker is installed on a monitored server, CVE-2026-33997 will appear in your dashboard with remediation steps.

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References

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