CVE-2026-39987
marimo Affected by Pre-Auth Remote Code Execution via Terminal WebSocket Authentication Bypass
CVSS Score
0.0
EPSS Score
7.0%
EPSS Percentile
91th
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.
| CWE | CWE-306 |
| Vendor | marimo-team |
| Product | marimo |
| Published | Apr 9, 2026 |
| Last Updated | Apr 24, 2026 |
⚠️ Actively Exploited — Act Now
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Affected Versions
marimo-team / marimo
< 0.23.0
References
github.com: https://github.com/marimo-team/marimo/security/advisories/GHSA-2679-6mx9-h9xc github.com: https://github.com/marimo-team/marimo/pull/9098 github.com: https://github.com/marimo-team/marimo/commit/c24d4806398f30be6b12acd6c60d1d7c68cfd12a sysdig.com: https://www.sysdig.com/blog/marimo-oss-python-notebook-rce-from-disclosure-to-exploitation-in-under-10-hours cisa.gov: https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-39987