dbcve.org
Composer Docker ImageApplication · Docker

CVE-2020-35184

CRITICAL · 9.8 CVSS v3.1 Published 2020-12-17
Fix available
A fix is available. Upgrade to 1.8.3 or later.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
The official composer docker images before 1.8.3 contain a blank password for a root user. System using the composer docker container deployed by affected versions of the docker image may allow a remote attacker to achieve root access with a blank password.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

The official Composer Docker images before version 1.8.3 contain a hardcoded blank password for the root user, creating a critical authentication bypass vulnerability. Attackers can remotely gain root access to affected containers by simply attempting login with an empty password.

MitigationImmediately upgrade to Composer Docker image version 1.8.3 or later and redeploy all affected containers. Verify that root access now requires proper authentication.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Composer Docker ImageApplication
Affected:< 1.8.3

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify if Composer Docker image is in use
    Review your docker-compose.yml files, Dockerfile instructions, or running containers (docker ps) to find any references to composer Docker images
    Affected if The image name contains 'composer' or is hosted on Docker Hub under the composer namespace
  2. Determine the installed Composer image version
    Run 'docker images' or 'docker inspect <container_id>' to see the exact image tag/version pulled
    Affected if The version tag is missing, 'latest', or shows a version number lower than 1.8.3 (e.g., 1.8.2, 1.8.1, 1.7.x, etc.)
  3. Test root access with empty password
    Attempt to access the container as root using SSH, docker exec, or the configured access method with a blank/empty password field
    Affected if Authentication succeeds with an empty password, granting root access without any credential
  4. Verify SSH or remote access configuration
    Check the container's SSH daemon configuration or any exposed management ports (usually 22) for authentication settings
    Affected if Root login is permitted and password authentication is enabled with no password set
  5. Inspect image history or Dockerfile if available
    Review the image build history (docker history) or any accompanying Dockerfile for hardcoded password directives or ROOT_PASSWORD settings
    Affected if The image contains instructions setting ROOT_PASSWORD to empty string or leaving password field blank

You are affected if you are running any version of the Composer Docker image prior to 1.8.3 and root access can be obtained using an empty password.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 1.8.3 or later
Fixed in 1.8.3
Interim mitigation

Immediately upgrade to Composer Docker image version 1.8.3 or later and redeploy all affected containers. Verify that root access now requires proper authentication.

Recommended fix High confidence

composer:1.8.3 or later

  1. Stop and remove any running containers using the affected composer docker image
  2. Pull the fixed version of the composer docker image: docker pull composer:1.8.3 (or use latest: docker pull composer:latest)
  3. Redeploy/recreate your containers using the new fixed image version
  4. Verify the root user now has a secure password configured in the image
  5. Test that your application functions correctly with the updated container image

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Composer Docker Image Scoped from the published advisory
  • Consultation3.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA1.0 h
10.0 hours of engineering $1,800
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An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,880.

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2020-35184 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data