GHSA-2JQ4-Q6VV-4CP3: Arbitrary File Write via Path Traversal in Crawl4AI Downloads

Vulnerability ID: GHSA-2JQ4-Q6VV-4CP3
CVSS Score: 9.6
Published: 2026-06-18

A critical Arbitrary File Write vulnerability exists in Crawl4AI versions 0.8.9 and below. By manipulating download filenames via Content-Disposition headers or suggested_filename values, attackers can write arbitrary files to any location on the file system, potentially leading to Remote Code Execution.

TL;DR

Crawl4AI <= 0.8.9 allows arbitrary file write and path traversal, potentially leading to RCE via unauthenticated /crawl endpoints or victim-initiated crawling.

⚠️ Exploit Status: POC

Technical Details

CWE ID: CWE-22, CWE-59
Attack Vector: Network (AV:N)
CVSS Score: 9.6 (Critical)
Impact: Arbitrary File Write / Remote Code Execution
Exploit Status: Proof-of-Concept
KEV Status: Not Listed

Affected Systems

Crawl4AI (Python package) <= 0.8.9
crawl4ai: <= 0.8.9 (Fixed in: 0.9.0)

Code Analysis

Commit: 60886d1

Secure-by-default hardening rewrite to address directory traversal and unsafe downloads

Mitigation Strategies

Upgrade the crawl4ai library to version 0.9.0 or higher.
Restrict execution privileges by running the crawler process as a non-root user.
Isolate the download directory to a dedicated, restricted volume.

Remediation Steps:

Run 'pip install --upgrade crawl4ai' to deploy the latest patched release.
Verify that the active deployment is running version 0.9.0 or later.
Implement the CRAWL4AI_API_TOKEN environment variable in Docker containers to secure API endpoints.