# CVE-2026-46562

## Summary

- **CVE ID:** CVE-2026-46562
- **Severity:** CRITICAL
- **CVSS Score:** 9.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)
- **CWE:** CWE-94, CWE-95, CWE-470
- **Published:** Jul 16, 2026
- **Last Modified:** Jul 16, 2026

## Description

Yamcs is a mission control framework. Prior to 5.12.7, the Nashorn ScriptEngine used to evaluate user-supplied JavaScript algorithm text in yamcs-core/src/main/java/org/yamcs/algorithms/ScriptAlgorithmExecutorFactory.java was constructed without a ClassFilter, so a user with the ChangeMissionDatabase privilege could override an algorithm through the MdbOverrideApi.updateAlgorithm endpoint and supply JavaScript that reaches arbitrary Java classes (for example Java.type("java.lang.Runtime").getRuntime().exec(...)) to execute arbitrary OS commands as the Yamcs process; in the default configuration with no security.yaml the built-in guest user has superuser=true, making the issue reachable without authentication. This issue is fixed in versions 5.12.7 and 5.13.0, which disable algorithm editing by default.

## Affected Products

- yamcs — yamcs (< 5.12.7)

## References

- [CNA](https://github.com/yamcs/yamcs/security/advisories/GHSA-vmwp-vh32-rj75)
- [CNA](https://github.com/yamcs/yamcs/commit/3c550348f866af4675d2ba4a51d8d12b7c7c6011)
- [CNA](https://github.com/yamcs/yamcs/commit/4ff8fda642ea8c3309a4d3f379aa77b763148992)
- [CNA](https://github.com/yamcs/yamcs/releases/tag/yamcs-5.12.7)
- [CNA](https://github.com/yamcs/yamcs/releases/tag/yamcs-5.13.0)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.98%
- **EPSS Percentile:** 60.0

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-11._