Vulnerability · Published Jun 30, 2026 · Assigned by VulnCheck

CVE-2026-56264Crawl4AI - Arbitrary JavaScript Execution via /execute_js Endpoint

High 8.1

In plain English

A high-severity code injection in Crawl4AI from Crawl4AI. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 42% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)8.1High

Exploit odds (30 days)0.5%top 57.8% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Crawl4AI before 0.8.7 contains an arbitrary JavaScript execution vulnerability in the Docker API server's /execute_js endpoint, which accepts and executes arbitrary user-supplied JavaScript in the server's browser context with --disable-web-security enabled. An attacker can execute arbitrary JavaScript and, combined with the browser's relaxed security settings, perform server-side request forgery against internal services.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
PyPI	crawl4ai	0.8.7	GHSA-365w-hqf6-vxfg
PyPI	crawl4ai	0.8.7	GHSA-8qrg-7j2f-rf2h
PyPI	crawl4ai	0.8.7	PYSEC-2026-229
PyPI	crawl4ai	0.8.7	PYSEC-2026-230
PyPI	crawl4ai	0.8.7	PYSEC-2026-239
PyPI	crawl4ai	0.8.7	PYSEC-2026-3443
PyPI	crawl4ai	0.8.7	PYSEC-2026-3449
PyPI	crawl4ai	0.8.7	PYSEC-2026-596
PyPI	crawl4ai	0.8.7	PYSEC-2026-798

Affected products (as reported)

Vendor	Product	Versions
Crawl4AI	Crawl4AI	0 – before 0.8.7

Weakness: CWE-94 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

References

https://github.com/unclecode/crawl4ai/security/advisories/GHSA-365w-hqf6-vxfg vendor-advisory
https://github.com/unclecode/crawl4ai product
VulnCheck Advisory: Crawl4AI - Arbitrary JavaScript Execution via /execute_js Endpoint third-party-advisory