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The vulnerability, CVE-2025-XXXXX, exists in the `resolve_ast_by_type` function of Llama Stack versions prior to v0.2.20. This function is responsible for processing and resolving elements of an Abstract Syntax Tree (AST) based on a given type. The flaw occurs because the function accepts user-supplied parameters without proper validation or sanitization. An attacker can craft a malicious payload containing arbitrary code or commands within these parameters. When the vulnerable function processes this tainted input, it fails to distinguish between legitimate data and executable instructions. This lack of input verification allows the injected code to be executed within the application’s context, potentially leading to full remote code execution on the host server if the application has sufficient privileges. The severity is moderated by the specific configuration and deployment environment.
Platform: Llama Stack
Version: prior to v0.2.20
Vulnerability: RCE
Severity: Moderate
date: 2025-09-24
Prediction: Patch expected by 2025-10-01
What Undercode Say:
Simulating parameter passing to the vulnerable function
curl -X POST http://target/api/resolve -d '{"type":"malicious", "params":"<ATTACKER_PAYLOAD>"}'
Example payload structure exploiting AST resolution
{
"ast_type": "UserControlled",
"data": "<strong>import</strong>('os').system('rm -rf /critical')"
}
How Exploit:
An attacker sends a specially crafted HTTP POST request to the endpoint utilizing the `resolve_ast_by_type` function. The malicious payload embedded within the request parameters is processed without sanitization, leading to execution of system commands on the target server.
Protection from this CVE:
Upgrade to Llama Stack v0.2.20 or later. Implement strict input validation and sanitization for all user-controlled parameters. Utilize security controls like Web Application Firewalls (WAFs) to filter malicious requests. Apply the principle of least privilege to the application service account.
Impact:
Remote Code Execution, potential complete system compromise, unauthorized data access or modification, and service disruption.
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Sources:
Reported By: github.com
Extra Source Hub:
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