JavaScript Injection Vulnerability in Crawl4AI by UncleCode
CVE-2026-119121

5.3MEDIUM

Key Information:

Vendor

Unclecode

Status
Crawl4ai
Vendor
CVE Published:
29 October 2026

What is CVE-2026-119121?

Crawl4AI versions prior to 0.9.5 are vulnerable to a JavaScript injection flaw within the Docker API server. Authenticated API clients can exploit this vulnerability to execute arbitrary JavaScript on the crawl page, leveraging manipulated inputs through allowlisted css_selector and wait_for fields. By injecting quotes into css_selector or using js: conditions within wait_for, attackers can bypass the js_code block, leading to unauthorized alterations of the page state and the content retrieved during the crawling process.

Affected Version(s)

crawl4ai 0.9.0 < 0.9.5

crawl4ai 0.9.5

References

https://github.com/unclecode/crawl4ai/security/advisories...
vendor-advisory
https://www.vulncheck.com/advisories/crawl4ai-0.9.0-befor...
third-party-advisory

CVSS V4

Score:
5.3
Severity:
MEDIUM
Confidentiality:
None
Integrity:
Low
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

manus-use
ntohidi
.