CVE-2026-46621criticalCWE-94

CVE-2026-46621: critical vulnerability in yamcs

Yamcs: Authenticated Remote Code Execution (RCE) via Jython Algorithm Code Injection

Published

Follow this CVE+ Monitor yamcs+ Monitor org.yamcs:yamcs-core

E-mail alert when it lands in KEV, gets a public PoC or its score goes up.

28Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 9.1epss 1.1%
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:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Affected products
yamcs · yamcs
Related CVEs — yamcs

In the same product, most dangerous first.

CVE-2026-44596MEDIUMYamcs: No Rate Limiting on Authentication EndpointEPSS 2.1%CVE-2026-55552HIGHYamcs: Unauthenticated Directory TraversalEPSS 1.7%CVE-2026-55549MEDIUMYamcs: Reflected XSS in the URL of the Authorize EndpointEPSS 1.3%CVE-2026-44632CRITICALYamcs: Server-Side Code Injection (RCE) via Janino Expression Engine in `JavaExprAlgorithmExecutionFactory`EPSS 1.1%CVE-2026-44595MEDIUMYamcs: Unauthorized user enumeration via IAM API endpointsEPSS 1.1%CVE-2026-42568MEDIUMYamcs Vulnerable to LDAP Injection in LdapAuthModuleEPSS 1.0%