CVE-2026-39987

Aliases:GHSA-2679-6MX9-H9XCGHSA-2679-6mx9-h9xc
Analyzed
Published: 09 Apr 2026, 17:16
Last modified:23 Apr 2026, 22:20

Vulnerability Summary

Overall Risk (default)
high
70/100
CVSS Score
9.8 CRITICAL
v3.1 (nvd)
EPSS Score
6.99% LOW
7% probability 0.00%
KEV
Listed
CISA
1 listing
Ransomware
No reports
Public exploits
2 found
Dark Web
Not detected

Timeline

09 Apr 2026, 17:16
Published
Vulnerability first disclosed
23 Apr 2026, 00:00
Added to CISA KEV
Marimo Remote Code Execution Vulnerability
23 Apr 2026, 22:20
Last Modified
Vulnerability information updated
07 May 2026, 00:00
CISA Remediation Due
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

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.

CVSS Metrics

  • v4.0•CRITICAL•Score: 9.3CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
  • v4.0•CRITICAL•Score: 9.3CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
  • v3.1•CRITICAL•Score: 9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Trends

Current EPSS score: 6.99%• Percentile: 91%

Techniques & Countermeasures

  • CWE-306•Missing Authentication for Critical Function

    The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.

Affected Systems

  • coreweave•marimo

    < 0.23.0

  • marimo-team•marimo

    < 0.23.0

  • PyPI•marimo

    < 0.23.0

References (8)