high CVSS 8.6

CVE-2026-26217·Docker vulnerability

Crawl4AI versions prior to 0.8.0 contain a local file inclusion vulnerability in the Docker API deployment. The /execute_js, /screenshot, /pdf, and /html endpoints accept file:// URLs, allowing unauthenticated remote attackers to read arbitrary files from the server filesystem. An attacker can access sensitive files such as /etc/passwd, /etc/shadow, application configuration files, and environment variables via /proc/self/environ, potentially exposing credentials, API keys, and internal application structure.

Severity
high
Software
Docker
Fixed in
0.8.0
Published
2026-02-12

Affected versions

Until: 0.8.0

Fixed in: 0.8.0

How to fix this CVE

Upgrade Docker to version 0.8.0 or later to patch the local file inclusion vulnerability in the API endpoints. This update removes the ability to use file:// URLs in the /execute_js, /screenshot, /pdf, and /html endpoints, preventing unauthorized filesystem access. Apply the update immediately as this vulnerability allows reading sensitive configuration files and credentials without authentication.

sudo dnf update docker-ce

Defensia detects this vulnerability

What an exploitation attempt looks like

Sample log line indicative of exploitation attempts:

POST|GET.*(/execute_js|/screenshot|/pdf|/html).*file://|file%3a%2f%2f

WAF mitigation (if patching is not yet possible)

Add this rule to your WAF to block exploitation attempts while you schedule the patch. 

Implement a Web Application Firewall rule that blocks any requests to /execute_js, /screenshot, /pdf, or /html endpoints containing 'file://' or URL-encoded variants (file%3a%2f%2f). Restrict these endpoints to authenticated users only and disable local file protocol handling.

How to check if you are affected

  1. Step 1: Check the installed Docker version by running: docker --version
  2. Step 2: List running Docker containers and inspect environment variables with: docker inspect <container_id> | grep -i 'env\|crawl4ai'
  3. Step 3: Review Docker API logs for POST/GET requests containing 'file://' in request paths: grep -r 'file://' /var/log/docker* /var/lib/docker/containers/*/*/json.log 2>/dev/null
  4. Step 4: Verify the patched version is installed by confirming docker --version shows a version from the 0.8.0 release branch or later

Indicators of compromise

  • /execute_js endpoint with file:// URL parameter
  • /screenshot endpoint with file:// URL parameter
  • /pdf endpoint with file:// URL parameter
  • /html endpoint with file:// URL parameter
  • file:///etc/passwd
  • file:///etc/shadow
  • file:///proc/self/environ

FAQ

What is CVE-2026-26217?

This is a local file inclusion (LFI) vulnerability in Docker's Crawl4AI API endpoints that permits unauthenticated attackers to retrieve arbitrary files from the server by submitting crafted file:// URLs to web endpoints, potentially exposing secrets and system configuration.

Is CVE-2026-26217 being actively exploited?

No, CVE-2026-26217 is not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog, and no public exploit code has been published.

What versions of Docker are affected by CVE-2026-26217?

All Docker versions prior to 0.8.0 are affected. Version 0.8.0 and later contain the fix.

How do I check if my server is vulnerable to CVE-2026-26217?

Run 'docker --version' and compare the version number against 0.8.0; if your version is older, you are vulnerable. Additionally, test if the API responds to file:// protocol requests on the vulnerable endpoints (/execute_js, /screenshot, /pdf, /html).

Does Defensia detect CVE-2026-26217?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Docker is installed on a monitored server, CVE-2026-26217 will appear in your dashboard with remediation steps.

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CVE-2026-42298CVSS 10Postiz is an AI social media scheduling tool. Prior to commit da44801, a "Pwn Request" vulnerability in the Build and Publish PR Docker Image workflow (.github/workflows/pr-docker-build.yml) allows any unauthenticated user to execute arbitrary code during the Docker build process and exfiltrate a highly privileged GITHUB_TOKEN (write-all permissions). This can be achieved simply by opening a Pull Request from a fork with a maliciously modified Dockerfile.dev. This issue has been patched via commit da44801.
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References

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