Blind Server-Side Request Forgery Vulnerability in Crawl4AI by Uncle Code
CVE-2026-109239

6.9MEDIUM

Key Information:

Vendor

Unclecode

Status
Crawl4ai
Vendor
CVE Published:
12 October 2026

What is CVE-2026-109239?

Crawl4AI versions before 0.9.4 are vulnerable to a blind server-side request forgery (SSRF) flaw in the RobotsParser.can_fetch feature. This weakness allows unauthenticated attackers to manipulate server requests, potentially bypassing Docker server egress controls. By enabling the check_robots_txt functionality, adversaries can leverage redirects or DNS rebinding techniques to access internal or loopback addresses, as well as cloud-metadata endpoints, facilitating unauthorized service discovery.

Affected Version(s)

crawl4ai 0 < 0.9.4

crawl4ai 0.9.4

References

https://github.com/unclecode/crawl4ai/security/advisories...
vendor-advisory
https://www.vulncheck.com/advisories/crawl4ai-before-0.9....
third-party-advisory

CVSS V4

Score:
6.9
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

arpe1618
.