Vulnerability Description
Yamcs is a mission control framework. Prior to 5.12.7, the Yamcs script evaluation engine for Python algorithms dynamically compiled and evaluated user-controlled algorithm text using Jython through the JSR-223 ScriptEngine API without enforcing a secure sandbox, so an authenticated user with the ChangeMissionDatabase privilege could override an existing Python algorithm's logic through the mission database REST API and import and execute arbitrary Java classes such as java.lang.Runtime to achieve remote code execution on the underlying host operating system. This issue is fixed in versions 5.12.7 and 5.13.0, which disable algorithm editing by default.
CVSS Score
CRITICAL
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Spaceapplications | Yamcs | < 5.12.7 |
Related Weaknesses (CWE)
References
- https://github.com/yamcs/yamcs/commit/3c550348f866af4675d2ba4a51d8d12b7c7c6011Patch
- https://github.com/yamcs/yamcs/commit/4ff8fda642ea8c3309a4d3f379aa77b763148992Patch
- https://github.com/yamcs/yamcs/releases/tag/yamcs-5.12.7Release Notes
- https://github.com/yamcs/yamcs/releases/tag/yamcs-5.13.0Release Notes
- https://github.com/yamcs/yamcs/security/advisories/GHSA-2g95-6x5q-xjwjExploitVendor Advisory
- https://github.com/yamcs/yamcs/security/advisories/GHSA-2g95-6x5q-xjwjExploitVendor Advisory
FAQ
What is CVE-2026-46621?
CVE-2026-46621 is a vulnerability with a CVSS score of 9.1 (CRITICAL). Yamcs is a mission control framework. Prior to 5.12.7, the Yamcs script evaluation engine for Python algorithms dynamically compiled and evaluated user-controlled algorithm text using Jython through t...
How severe is CVE-2026-46621?
CVE-2026-46621 has been rated CRITICAL with a CVSS base score of 9.1/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2026-46621?
Check the references section above for vendor advisories and patch information. Affected products include: Spaceapplications Yamcs.