Blackfire Docker ImageApplication · Blackfire

CVE-2020-35466

CRITICAL · 9.8 CVSS v3.1 Published 2020-12-15
Fix available
A fix is available. Upgrade to after 2020-12-14 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 Blackfire Docker image through 2020-12-14 contains a blank password for the root user. Systems deployed using affected versions of the Blackfire container 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 Blackfire Docker image through December 2020 was distributed with a blank (empty) password for the root user. Any system running this container image allowed remote attackers to authenticate as root without a password, achieving full system compromise.

MitigationUpdate to a patched Blackfire Docker image released after 2020-12-14 and ensure all deployed containers use the updated image with proper root password configuration.

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
Blackfire Docker ImageApplication
Affected:<= 2020-12-14

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 Blackfire containers
    Run 'docker ps -a | grep -i blackfire' to list any running or stopped Blackfire containers
    Affected if Any Blackfire container exists in the environment
  2. Check the Blackfire image version
    Run 'docker images | grep blackfire' to list local Blackfire images, then inspect the tag with 'docker images --format "{{.Repository}}:{{.Tag}} {{.CreatedAt}}" | grep blackfire'
    Affected if The image tag or creation date indicates a version created on or before December 14, 2020
  3. Verify container root access method
    If a Blackfire container is running, attempt to access it via 'docker exec -it <container_id> /bin/sh' or check if SSH service is configured inside the container
    Affected if Root shell access is available without being prompted for a password
  4. Review container deployment configuration
    Check docker-compose files, Kubernetes manifests, or CI/CD pipelines that reference the Blackfire Docker image for the image tag or date
    Affected if The deployment references an untagged 'blackfire' image or a tag dated 2020-12-14 or earlier

The environment is affected if a Blackfire Docker container is running from an image built on or before 2020-12-14, which would allow unauthenticated root access.

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.

From vendor data
Upgrade available Upgrade to a release after 2020-12-14
Interim mitigation

Update to a patched Blackfire Docker image released after 2020-12-14 and ensure all deployed containers use the updated image with proper root password configuration.

Fix this in Blackfire Docker Image Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing2.0 h
6.0 hours of engineering $1,060
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,696.

Scan for this in your stack

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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-2020-35466 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