CVE-2026-39987
critical · 9.3Actively exploitedOn the CISA Known Exploited Vulnerabilities catalog
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
A public exploit / detection template exists
Weaponised detection is publicly available, which meaningfully raises real-world risk regardless of CVSS. nuclei-templates →
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: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
Weaknesses
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| coreweave | marimo | < 0.23.0 |
Check a specific version with /api/v1/cve/match.
References
- https://github.com/marimo-team/marimo/commit/c24d4806398f30be6b12acd6c60d1d7c68cfd12a
- https://github.com/marimo-team/marimo/pull/9098
- https://github.com/marimo-team/marimo/security/advisories/GHSA-2679-6mx9-h9xc
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-39987
- https://www.sysdig.com/blog/marimo-oss-python-notebook-rce-from-disclosure-to-exploitation-in-under-10-hours
Query this programmatically:
curl https://evil-db.io/api/v1/cve/CVE-2026-39987