CVE-2026-46562 Yamcs: Remote Code Execution via Mission Database algorithm override
Attackers can execute arbitrary OS commands via JavaScript injection in Yamcs mission database algorithms, especially when default guest access is enabled.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-46562?
CVE-2026-46562 is a critical code injection vulnerability in yamcs, published on 16 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Which versions are affected by CVE-2026-46562?
2 open source packages ship an affected version, including org.yamcs:yamcs-core. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
org.yamcs:yamcs-core Maven | All versions | 5.12.7 |
org.yamcs:yamcs-core Maven | All versions | 5.12.7 |
Products include Spaceapplications Yamcs.
How do I fix CVE-2026-46562?
Upgrade org.yamcs:yamcs-core to 5.12.7 or later.
Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.
Is CVE-2026-46562 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-46562 exists.
Other vulnerabilities in yamcs
- CVE-2026-44632 Yamcs: Server-Side Code Injection (RCE) via Janino Expression Engine in `JavaExprAlgorithmExecutionFactory`
- CVE-2026-46621 Yamcs: Authenticated Remote Code Execution (RCE) via Jython Algorithm Code Injection
- CVE-2023-45278 Yamcs API Directory Traversal vulnerability
- CVE-2023-45277 Yamcs Path Traversal vulnerability
- CVE-2026-44596 Yamcs: No Rate Limiting on Authentication Endpoint
Sources
Also known as GHSA-vmwp-vh32-rj75.