HIGH CVSS 7.2
Published: 2026-06-12

CVE-2026-42306

docker engine Security Advisory (CVE-2026-42306)
↗ Official NIST NVD Record
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CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2026-42306 impacting docker engine. Evaluated with CVSS Base Score of 7.2 (HIGH).

Original NVD Description

Source: NIST NVD
Moby is an open source container framework. In Docker Engine prior to version 29.5.1, Docker Daemon versions 28.5.2 and prior, and Moby Daemon prior to version 2.0.0-beta.14, a race condition during docker cp mount setup allows a malicious container to redirect a bind mount target to an arbitrary host path, potentially overwriting host files or causing denial of service. This issue has been patched in Docker Engine version 29.5.1 and Moby Daemon version 2.0.0-beta.14.

📊 CVSS v3.1 Metric Breakdown

Attack Vector
Local (AV:L)
Requires local system execution permissions
Attack Complexity
High (AC:H)
Depends on race conditions or environment
Privileges Required
Low (PR:L)
Standard user access required
User Interaction
Required (UI:R)
User must click or open resource
Scope
Changed (S:C)
Impacts components beyond caller authority
Confidentiality
None (C:N)
No data confidentiality impact
Integrity
High (I:H)
Total modification of target system
Availability
High (A:H)
Total denial of service or shutdown

🎯 Affected Versions Matrix

Affected Product docker / engine
Affected Versions *
Weakness Enumeration CWE-61

Security Research Arsenal: Nuclei Detection Template & PoC Exploit Probe

High-Intent Research Tool

Ready-to-use security scanner signatures, active verification probe skeletons, and remediation playbooks for CVE-2026-42306 impacting docker engine.

⚡ Nuclei Detection Template (YAML) cve-2026-42306.yaml
id: cve-2026-42306

info:
  name: docker engine - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: high
  description: |
    Automated signature & scanner for CVE-2026-42306 affecting docker engine.
    Evaluation: Moby is an open source container framework. In Docker Engine prior to version 29.5.1, Docker Daemon versions 28.5.2 and prior, and Moby Daemon prior t...
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2026-42306
  classification:
    cvss-metrics: CVSS:3.1/CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:N/I:H/A:H
    cvss-score: 7.2
    cve-id: CVE-2026-42306
    cwe-id: CWE-61
  tags: cve,cve-2026-42306,docker,engine,high

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "engine"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2026-42306.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2026-42306
# Target: docker engine | CVSS: 7.2 (HIGH)
# Educational & Security Audit Purpose Only

import requests
import sys

def verify_vulnerability(target_url):
    print(f"[*] Auditing {target_url} for CVE-2026-42306 (docker engine)...")
    headers = {
        "User-Agent": "CyberVault-Audit-Scanner/2.0",
        "Accept": "*/*"
    }
    try:
        r = requests.get(f"{target_url.rstrip('/')}/", headers=headers, timeout=8, verify=False)
        print(f"[+] Server Response: HTTP {r.status_code} | Server Banner: {r.headers.get('Server', 'Unknown')}")
        if r.status_code < 500:
            print(f"[!] Target reachable. Verify version against docker engine scope (*).")
        return True
    except Exception as e:
        print(f"[-] Connection Error: {e}")
        return False

if __name__ == '__main__':
    url = sys.argv[1] if len(sys.argv) > 1 else "http://localhost:8080"
    verify_vulnerability(url)
🛡️ Quick Patch & Remediation Script (Bash) patch_cve-2026-42306.sh
# Recommended Remediation & Patching Commands for CVE-2026-42306
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install engine 2>/dev/null || \
sudo dnf upgrade engine 2>/dev/null || \
sudo yum update engine

# 2. Inspect installed package versions for vulnerable scope:
dpkg -l | grep -i engine 2>/dev/null || rpm -qa | grep -i engine

# 3. Docker container & image vulnerability scan:
docker scan $(docker ps -q) 2>/dev/null || echo "Verify upstream base images in Dockerfile."

🛡️ Remediation & Security Action

  • Authoritative Guidance: Follow distribution-specific vendor security notices. Advisory status and package patches vary by distribution release.
  • Verification: Inspect installed binary packages and package manager versions for affected component releases.
  • Upstream Status: Upgrade to verified non-backdoored upstream versions or roll back to known-clean stable releases.
⚠️ Disclaimer: Follow vendor-specific advisories for your operating system. CyberVault does not fabricate unsupported remediation scripts.

🔗 Verified Technical References

Authorities
  • No records filed in this category.
Distributions
  • No records filed in this category.

❓ Frequently Asked Questions (FAQ) & Remediation Guide

How do I fix CVE-2026-42306 in docker engine?

Review vendor-specific security notices and update docker engine packages to the latest patched release immediately. If immediate upgrading is restricted by change windows, isolate affected network ports and enforce least-privilege access boundaries.

Is there an active exploit or public PoC for CVE-2026-42306?

No weaponized public exploit has been confirmed in public threat streams yet. Continuous surveillance is active across GitHub and security feeds.

What is the CVSS 3.1 severity rating and impact for CVE-2026-42306?

CVE-2026-42306 is classified with a CVSS 3.1 Base Score of 7.2 (HIGH). Check the metric breakdown above for attack vector requirements.

Risk Snapshot
7.2
HIGH SEVERITY
CVE ID CVE-2026-42306
Weakness CWE-61
Vendor docker
Product engine
Published 2026-06-12
Vector CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:N/I:H/A:H