CVE-2026-39987

marimo is a reactive Python notebook. Prior to 0.23.0, Marimo has a Pre-Auth RCE vulnerability. The terminal WebSocket endpoint /terminal/ws lacks authentication validation, allowing an unauthenticated attacker to obtain a full PTY shell and execute arbitrary system commands. Unlike other WebSocket endpoints (e.g., /ws) that correctly call validate_auth() for authentication, the /terminal/ws endpoint only checks the running mode and platform support before accepting connections, completely skipping authentication verification. This vulnerability is fixed in 0.23.0.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/marimo-team/marimo/commit/c24d4806398f30be6b12acd6c60d1d7c68cfd12a	Patch
https://github.com/marimo-team/marimo/pull/9098	Issue Tracking Patch
https://github.com/marimo-team/marimo/security/advisories/GHSA-2679-6mx9-h9xc	Exploit Mitigation Vendor Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-39987	US Government Resource
https://www.sysdig.com/blog/marimo-oss-python-notebook-rce-from-disclosure-to-exploitation-in-under-10-hours	Exploit Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:coreweave:marimo:*:*:*:*:*:python:*:*

History

No history.

Information

Published : 2026-04-09 18:17

Updated : 2026-06-17 10:42

NVD link : CVE-2026-39987

Mitre link : CVE-2026-39987

CVE.ORG link : CVE-2026-39987

JSON object : View

Products Affected

coreweave

marimo

CWE

CWE-306

Missing Authentication for Critical Function

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