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.

Related Docker CVEs

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CVE-2026-57572CVSS 10Crawl4AI is an open-source LLM-friendly web crawler and scraper. Prior to 0.9.0, the Docker API server accepted request-supplied browser_config.extra_args, which flowed into Chromium's launch arguments. An attacker could inject Chromium switches that replace a child-process launch command together with --no-zygote, causing Chromium to fork or exec an attacker-controlled command as the container's runtime user. The Docker API is unauthenticated by default, so a single request yields arbitrary command execution. This issue is fixed in version 0.9.0.
CVE-2026-53576CVSS 10Kestra is an open-source, event-driven orchestration platform. Prior to 1.0.45 and 1.3.21, the authentication filter for the REST API (@Filter("/api/v1/**")) treats any request whose path ends in /configs as the public instance-config endpoint and forwards it without a credential check. kestra addresses its resources by URL path segments that the caller chooses (/api/v1/{tenant}/flows/{namespace}, /api/v1/{tenant}/executions/{namespace}/{id}, /api/v1/{tenant}/namespaces/{namespace}/kv/{key}). An anonymous caller picks the literal configs as the final segment, and the request bypasses Basic-Auth entirely. Because the bypass reaches the flow-create and execution-trigger routes, an unauthenticated caller creates a flow containing a Shell or Process task and runs it. The task executes as root inside the kestra container. The official docker-compose.yml mounts /var/run/docker.sock, so root in the container reaches the host Docker daemon. This vulnerability is fixed in 1.0.45 and 1.3.21.
CVE-2026-33587CVSS 10Lack of user input sanitisation in Open Notebook v1.8.3 allows the application user to execute Python code (and subsequently OS commands) on the docker container via Server-Side Template Injection (SSTI) for user-created transformations.
CVE-2026-26216CVSS 10Crawl4AI versions prior to 0.8.0 contain a remote code execution vulnerability in the Docker API deployment. The /crawl endpoint accepts a hooks parameter containing Python code that is executed using exec(). The __import__ builtin was included in the allowed builtins, allowing unauthenticated remote attackers to import arbitrary modules and execute system commands. Successful exploitation allows full server compromise, including arbitrary command execution, file read and write access, sensitive data exfiltration, and lateral movement within internal networks.

References

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