Marimo · Marimo
CVE-2026-39987
marimo Affected by Pre-Auth Remote Code Execution via Terminal WebSocket Authentication Bypass
Qué es
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.
CISA: Marimo contains an pre-authorization remote code execution vulnerability, allowing an unauthenticated attacked to shell access and execute arbitrary system commands.
Qué hacer
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Plazo para las agencias federales de EE. UU.: 7 de mayo de 2026
Fuentes: Known Exploited Vulnerabilities (CISA, dominio público), CVE records (cve.org) y EPSS (FIRST). La probabilidad de ataque es la estimación EPSS de que alguien intente explotar el fallo en los próximos 30 días.