Vulnerability in Marimo-Team Marimo

CVE-2026-67618

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.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.003 (22.1th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 22nd percentile — 22.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-67618: held from 0.003 to 0.003.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-67618?
CVE-2026-67618 is a medium-severity vulnerability in Marimo-Team Marimo, classified under Insufficient Verification of Data Authenticity. CVSS score: 6.5/10. Published 2026-08-04.
How severe is CVE-2026-67618?
Medium severity. CVSS v3 base score is 6.5 out of 10.