CVE-2026-53753
CRITICAL EPSS 35.9%
Published Jun 23, 20261w ago · Modified Jun 23, 20261w ago
9.8 CVSS 3.1
Published Jun 23, 2026 1w ago
Last Modified Jun 23, 2026 1w ago
Description
Crawl4AI is an open-source LLM friendly web crawler & scraper. Prior to 0.8.7, the _safe_eval_expression() function in the computed fields feature uses an AST validator that only blocks attributes starting with underscore. Python generator and frame object attributes (gi_frame, f_back, f_builtins) do NOT start with underscore, enabling a complete sandbox escape to achieve arbitrary code execution. The attack requires no authentication (JWT disabled by default) and is triggered via POST /crawl with a crafted extraction schema. This vulnerability is fixed in 0.8.7.
CVSS Details
Base Score
Exploitability
Impact
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality High
Integrity High
Availability High
Threat Intelligence
EPSS Exploit Probability
35.9% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available
Weaknesses 2
CWE-913
CWE-94 Improper Control of Generation of Code (Code Injection) Injection
References 1
- github.com https://github.com/unclecode/crawl4ai/security/advisories/GHSA-qxjp-w3pj-48m7
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.