high CVSS 8.2

CVE-2026-56259·Docker vulnerability

Crawl4AI before 0.8.8 contains credential exfiltration vulnerabilities in the Docker API server that allow attackers to redirect LLM API calls to attacker-controlled endpoints and read arbitrary environment variables. Attackers can exploit the unauthenticated /md, /llm, and /llm/job endpoints by supplying a malicious base_url parameter and setting api_token to env:VARIABLE_NAME to exfiltrate provider API keys and server secrets including JWT SECRET_KEY for authentication bypass.

Severity
high
Software
Docker
Fixed in
0.8.8
Published
2026-07-12

Affected versions

Until: 0.8.8

Fixed in: 0.8.8

How to fix this CVE

Update Docker to version 0.8.8 or later to patch the credential exfiltration vulnerability affecting the Crawl4AI LLM endpoints. The vulnerability allows unauthenticated attackers to redirect API calls and extract sensitive environment variables including authentication tokens. Immediate patching is critical if your Docker deployment exposes the /md, /llm, or /llm/job endpoints to untrusted networks.

sudo dnf update docker-ce

Defensia detects this vulnerability

What an exploitation attempt looks like

Sample log line indicative of exploitation attempts:

POST|GET /llm\?.*base_url=http|GET /md\?.*base_url=http|/llm/job\?.*api_token=env:

WAF mitigation (if patching is not yet possible)

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

Block or rate-limit requests to /md, /llm, and /llm/job endpoints containing base_url parameters pointing to external hosts; require authentication tokens and validate that api_token values do not contain the 'env:' prefix pattern.

How to check if you are affected

  1. Run 'docker --version' to check your current Docker version; versions prior to 0.8.8 are vulnerable
  2. Execute 'netstat -tuln | grep -E ":(80|443|8000|8080)"' to identify exposed ports and check if Crawl4AI endpoints are publicly accessible without authentication
  3. Search Docker logs with 'grep -i "base_url\|env:" /var/log/docker.log /var/lib/docker/containers/*/*.log' to find suspicious base_url parameter usage or environment variable resolution attempts
  4. Verify patched version by running 'docker --version' again after update and confirm the version number is 0.8.8 or higher

Indicators of compromise

  • HTTP requests with 'base_url=' parameter pointing to non-localhost IP addresses
  • api_token parameter values matching pattern 'env:*'
  • POST/GET requests to /llm, /llm/job, or /md endpoints from non-whitelisted IP ranges

FAQ

What is CVE-2026-56259?

CVE-2026-56259 is a credential exfiltration vulnerability in Crawl4AI's Docker API endpoints that allows unauthenticated attackers to steal sensitive environment variables and authentication tokens by manipulating the base_url parameter and using environment variable injection syntax.

Is CVE-2026-56259 being actively exploited?

No, this vulnerability is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog and no public exploits are currently available, though the attack method is straightforward and remediation should not be delayed.

What versions of Docker are affected by CVE-2026-56259?

All versions of Docker/Crawl4AI prior to 0.8.8 are affected; the exact lower bound is not specified but the vulnerability impacts unknown earlier versions through 0.8.8.

How do I check if my server is vulnerable to CVE-2026-56259?

Run 'docker --version' and compare the output to version 0.8.8; if your version is lower, you are vulnerable. Additionally, run 'docker ps' and check if containers expose ports 8000 or 8080 that serve the /md, /llm, or /llm/job endpoints to untrusted networks.

Does Defensia detect CVE-2026-56259?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Docker is installed on a monitored server, CVE-2026-56259 will appear in your dashboard with remediation steps.

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References

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