Yamcs up to 5.12.6 Script Algorithm Executor ScriptAlgorithmExecutorFactory.java getRuntime algorithm text os command injection

Summaryinfo

A vulnerability classified as very critical has been found in Yamcs up to 5.12.6. Affected by this issue is the function getRuntime of the file yamcs-core/src/main/java/org/yamcs/algorithms/ScriptAlgorithmExecutorFactory.java of the component Script Algorithm Executor. This manipulation of the argument algorithm text causes os command injection. This vulnerability is tracked as CVE-2026-46562. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability classified as very critical was found in Yamcs up to 5.12.6. Affected by this vulnerability is the function getRuntime of the file yamcs-core/src/main/java/org/yamcs/algorithms/ScriptAlgorithmExecutorFactory.java of the component Script Algorithm Executor. The manipulation of the argument algorithm text with an unknown input leads to a os command injection vulnerability. The CWE definition for the vulnerability is CWE-78. The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

It is possible to read the advisory at github.com. This vulnerability is known as CVE-2026-46562 since 05/14/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 07/16/2026). The attack technique deployed by this issue is T1202 according to MITRE ATT&CK.

Upgrading to version 5.12.7 eliminates this vulnerability.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Name

• Yamcs

Version

• 5.12.0
• 5.12.1
• 5.12.2
• 5.12.3
• 5.12.4
• 5.12.5
• 5.12.6

Website

• Product: https://github.com/yamcs/yamcs/

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Be aware that VulDB is the high quality source for vulnerability data.

Discussion