marimo before 0.23.15 contains a configuration injection vulnerability that allows notebook authors to exfiltrate operator API keys by embedding a malicious base_url in PEP-723 inline script metadata, which is merged into session configuration with higher precedence than the operator's own settings due to insufficient sanitization in sanitize_pyproject_dict. When an operator opens the crafted notebook and makes an AI request, marimo resolves the attacker-controlled base_url from the notebook config while falling back to the operator's OPENAI_API_KEY environment variable for authentication, transmitting the API key to the attacker-controlled endpoint without requiring any cell execution.
{
"cna_assigner": "VulnCheck",
"cwe_ids": [
"CWE-345"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/67xxx/CVE-2026-67618.json"
}