CVE-2026-46621CWE-94

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

Critical · published July 16, 2026

CVSS v3.1
9.1
EPSS
1%
Percentile
65.9
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
9.1 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.01116 · 65.9th percentile
Weakness
CWE-94 · Improper Control of Generation of Code ('Code Injection')
Published
2026-07-16T16:07Z
EPSS history
Timeline
  • 16 JUL 16:07Z
    Yamcs: Authenticated Remote Code Execution (RCE) via Jython Algorithm Code Injection
    cvelistv5