Live Exposure Defense: From CVE to Confirmed Exposure in 12 Hours – See more

Back
New CVE Detected

CVE-2026-56264 – Arbitrary JavaScript Execution and SSRF – Crawl4AI before 0.8.7

Be the first to know when new zero-days emerge:

Subscribe to Email Alerts
Subscribe to RSS Feed

Summary

CVE-2026-56264 is a critical code injection vulnerability (CWE-94) affecting the Crawl4AI Docker API server in all versions prior to 0.8.7. The /execute_js endpoint accepts and executes arbitrary user-supplied JavaScript inside the server’s Chromium browser instance, which is launched with the --disable-web-security flag, eliminating cross-origin restrictions. With a CVSS 4.0 score of 9.2, unauthenticated remote attackers can exploit this to execute arbitrary JavaScript and perform server-side request forgery (SSRF) against internal services, cloud metadata endpoints, and Docker-networked hosts.

Technical details

  • Root cause: The /execute_js endpoint in the Crawl4AI Docker API server performs no input validation before executing caller-supplied JavaScript directly inside a server-side Chromium browser instance.
  • Compounding factor: The browser is launched with the --disable-web-security flag, which removes same-origin policy enforcement and cross-origin restrictions, allowing injected scripts to reach resources they would normally be blocked from accessing.
  • Attack vector: An unauthenticated attacker sends a crafted POST request to the /execute_js endpoint with a malicious JavaScript payload. No credentials are required — the Docker API server has authentication disabled by default (jwt_enabled: false).
  • Impact: Executed JavaScript can probe internal Docker-networked services, query cloud metadata endpoints such as 169.254.169.254 to harvest cloud credentials, and exfiltrate sensitive data, enabling SSRF and lateral movement within the host’s internal network.

Affected software

  • Crawl4AI (PyPI package crawl4ai) — all versions before 0.8.7 (versions 0.x through 0.8.6 inclusive)
  • Specifically affects deployments running the Crawl4AI Docker API server (default port 11235)

Severity

  • CVSS 4.0: 9.2 CRITICAL — CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
  • CVSS 3.1: 8.1 HIGH — CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Mitigation and recommended actions

  • Immediate: Upgrade to Crawl4AI 0.8.7 or later. Version 0.8.7 disables the /execute_js endpoint by default (opt-in via the CRAWL4AI_EXECUTE_JS_ENABLED environment variable), removes --disable-web-security from the default browser arguments, and applies SSRF destination blocklisting across all API endpoints.
  • If immediate patching is not possible: Restrict network access to the Crawl4AI Docker API server (default port 11235) using firewall rules or network segmentation so it is not reachable from untrusted hosts. Do not expose the API server directly to the public internet.

IONIX Status

The IONIX research team is tracking ongoing exploitation attempts and recommends immediate patching. Potentially affected assets are outlined in this post.

References

Are you exposed?

Get a free report of your organization’s exposure to this CVE and threat

  • Mapping of all Assets with this Technology
  • Identification of potentially exposed assets to this CVE
  • Confirmation of verified exploitable assets
Get Exposure Report

How IONIX’s External Exposure Management Platform Detects and Validates
Zero-Days to Shrink MTTR

1

Map your entire attack surface (continously)

IONIX uses multi-factor discovery methods, including DNS analysis, certificate mapping, metadata inspection, and more, to automatically map every internet-facing asset across your environment. This includes cloud instances, third-party platforms, shadow IT, and even forgotten infrastructure that traditional tools miss.

2

Monitor for new CVEs

Dozens of threat intel feeds using agentic technology are continuously analyzed to detect the appearance of proof-of-concept code, exploit kits, and indicators of active targeting. IONIX goes further by applying AI to proactively evaluate whether emerging vulnerabilities are likely to be exploited, even before PoCs go public.

3

Identify Potential External Exposures

Not all CVEs matter. IONIX filters vulnerabilities by asking attacker-centric questions: Can it be reached from the internet? Does it require authentication? Is it being exploited in the wild? This dramatically reduces noise and focuses teams on threats that can actually be weaponized.

4

Create Safe, Scalable Exploit Validations

IONIX transforms real-world PoCs into safe, non-intrusive test payloads that can be run in production environments without disruption. These simulations are precisely targeted to the systems that are vulnerable, ensuring rapid validation without unnecessary load.

5

Execute Exploit Validations

By combining context about software stack, versioning, exposure status, and reachability, IONIX ensures that only the right payloads are executed against the right assets, maximizing efficiency and minimizing risk.

6

Drive Fast and Actionable Remediation

Results are routed through integrations with ticketing, SOAR, and SIEM tools. Issues are written in plain language, bundled into remediation clusters, and prioritized based on asset criticality, exploitability, and blast radius. This shortens mean time to remediation (MTTR) and empowers teams to act with confidence.

Are you exposed?

Get a free report of your organization’s exposure to this CVE and threat

  • Mapping of all Assets with this Technology
  • Identification of potentially exposed assets to this CVE
  • Confirmation of verified exploitable assets
Get Exposure Report
Close

Subscribe to Threat Center RSS

Copy/paste the link below into your preferred RSS reader or follow these instructions to subscribe to Slack alerts.

Open RSS feedSlack setup instructions

Close

Get Real-Time CVE Alerts to Your Email

Be the first to know when new zero-days emerge