CVE-2026-46621
CRITICALYamcs: Authenticated Remote Code Execution (RCE) via Jython Algorithm Code Injection
Title source: cnaDescription
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.
References (5)
Core 5
Core References
X_Refsource_Confirm x_refsource_confirm
https://github.com/yamcs/yamcs/security/advisories/GHSA-2g95-6x5q-xjwj
X_Refsource_Misc x_refsource_misc
https://github.com/yamcs/yamcs/commit/3c550348f866af4675d2ba4a51d8d12b7c7c6011
X_Refsource_Misc x_refsource_misc
https://github.com/yamcs/yamcs/commit/4ff8fda642ea8c3309a4d3f379aa77b763148992
X_Refsource_Misc x_refsource_misc
https://github.com/yamcs/yamcs/releases/tag/yamcs-5.12.7
X_Refsource_Misc x_refsource_misc
https://github.com/yamcs/yamcs/releases/tag/yamcs-5.13.0
Scores
CVSS v3
9.1
EPSS
0.0100
EPSS Percentile
59.3%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
CISA SSVC
Vulnrichment
Exploitation
poc
Automatable
no
Technical Impact
total
Details
CWE
CWE-94
Status
published
Products (2)
spaceapplications/yamcs
< 5.12.7
yamcs/yamcs
< 5.12.7
Published
Jul 16, 2026
Tracked Since
Jul 16, 2026