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

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-2026-53576CVSS 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-2026-44182CVSS 10Jupyter Enterprise Gateway launches remote Jupyter Notebook kernels across distributed clusters like Apache Spark, Kubernetes, and Docker Swarm. In versions prior to 3.3.0, the server interpolates untrusted environment variables (e.g., KERNEL_XXX) into Kubernetes manifests without YAML-aware escaping, enabling YAML injection attacks. Attackers can inject new fields, overwrite critical fields (e.g., duplicate securityContext keys, where the last one prevails), and inject document boundaries (--- for new documents, ... for end-of-document) to generate multiple resources, potentially creating arbitrary types, such as privileged pods. The Jinja2 template for the Kubernetes manifest contains several kernel_xxx variables, such as kernel_working_dir that are used when rendering the manifest and are all vectors for YAML injection. This issue has been fixed in version 3.3.0.
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.
CVE-2026-44329CVSS 10free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's SMF mounts the UPI management route group without OAuth2/bearer-token authorization middleware. A network attacker who can reach SMF on the SBI can hit UPI endpoints with no Authorization header at all, and the requests reach the SMF business handlers. In the running Docker lab this was directly demonstrated for read (GET /upi/v1/upNodesLinks), write (POST /upi/v1/upNodesLinks with attacker-controlled UP-node and link payload), and delete (DELETE /upi/v1/upNodesLinks/{nodeID}) operations. This vulnerability is fixed in 4.2.2.

References

Track CVEs across your fleet automatically

Defensia scans your Linux servers and tells you exactly which ones are running vulnerable versions — including CVE-2026-26217. Free for 1 server.

Get started free