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.
History

Fri, 10 Apr 2026 09:00:00 +0000

Type Values Removed Values Added
First Time appeared Marimo-team
Marimo-team marimo
Vendors & Products Marimo-team
Marimo-team marimo

Thu, 09 Apr 2026 19:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Thu, 09 Apr 2026 17:30:00 +0000

Type Values Removed Values Added
Description 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.
Title marimo Affected by Pre-Auth Remote Code Execution via Terminal WebSocket Authentication Bypass
Weaknesses CWE-306
References
Metrics cvssV4_0

{'score': 9.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-04-09T17:44:29.019Z

Reserved: 2026-04-08T00:01:47.629Z

Link: CVE-2026-39987

cve-icon Vulnrichment

Updated: 2026-04-09T17:43:39.571Z

cve-icon NVD

Status : Received

Published: 2026-04-09T18:17:02.807

Modified: 2026-04-09T18:17:02.807

Link: CVE-2026-39987

cve-icon Redhat

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