SECURELYN

CVE-2026-77602

OpenC3 COSMOS provides the functionality needed to send commands to and receive data from one or more embedded systems. From 5.1.0 until 7.3.0, authenticated non-administrator users can write content under targets_modified/ that is later executed by multiple configuration paths below the intended code-execution privilege tier. Table and command or telemetry definitions are processed through ConfigParser, PacketConfig, GENERIC_READ_CONVERSION, or GENERIC_WRITE_CONVERSION, allowing ERB rendering or Ruby and Python evaluation, while openc3-cosmos-script-runner-api/scripts/run_suite_analysis.rb e…

Scores

9.9
CVSS 9.9 out of 10, critical severity.
0.6%
EPSS 0.6% chance of exploitation in the next 30 days.

The facts

Published
23 September 2026
Last changed
29 September 2026
NVD status
Deferred
Severity
Critical, CVSS 9.9 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Weakness
Known exploited
Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
EPSS
0.6% chance of exploitation activity in the next 30 days (percentile 46).

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References