RCE in Spaceapplications Yamcs
CVE-2026-46562
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.
Vulnerability class: RCE (Remote Code Execution)
EPSS: 0.010 (59.1th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Spaceapplications Yamcs
- Yamcs — versions < 5.12.7
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Vendor Advisory)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC, Release Notes)
- security-advisories@github.com (x_refsource_MISC, Release Notes)
Frequently asked questions
- What is CVE-2026-46562?
- CVE-2026-46562 is a critical-severity vulnerability in Spaceapplications Yamcs, classified under Code Injection. CVSS score: 9.8/10. Published 2026-07-16.
- How severe is CVE-2026-46562?
- Critical severity. CVSS v3 base score is 9.8 out of 10.