CVE-2026-39987
KEVMarimo Remote Code Execution Vulnerability
9.3
CriticalPublished:
Last updated:
Source:security-advisories@github.com
Analyzed
Weakness (CWE)
CVSS Vector
v4.0- Attack Vector
- Network
- Attack Complexity
- Low
- Attack Requirements
- None
- Privileges Required
- None
- User Interaction
- None
- Confidentiality (Vulnerable)
- High
- Integrity (Vulnerable)
- High
- Availability (Vulnerable)
- High
- Confidentiality (Subsequent)
- None
- Integrity (Subsequent)
- None
- Availability (Subsequent)
- None
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.
References
security-advisories@github.com
https://github.com/marimo-team/marimo/commit/c24d4806398f30be6b12acd6c60d1d7c68cfd12asecurity-advisories@github.com
https://github.com/marimo-team/marimo/pull/9098security-advisories@github.com
https://github.com/marimo-team/marimo/security/advisories/GHSA-2679-6mx9-h9xc134c704f-9b21-4f2e-91b3-4a467353bcc0
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-39987134c704f-9b21-4f2e-91b3-4a467353bcc0
https://www.sysdig.com/blog/marimo-oss-python-notebook-rce-from-disclosure-to-exploitation-in-under-10-hours