๐Ÿ” CVE Alert

CVE-2026-77602

CRITICAL 9.9

OpenC3 COSMOS: Authenticated remote code execution via the user-writable config overlay (table definitions, cmd/tlm definitions, and script suites)

CVSS Score
9.9
EPSS Score
0.0%
EPSS Percentile
0th

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 executes suite procedure files through require. Storage uploads, screen saves, and script creation can place content in the overlay, and triggering table processing, a cmd/tlm reload, or suite analysis executes the content in cmd-tlm-api, decom microservices, or Script Runner with access to internal credentials and data. This issue is fixed in version 7.3.0.

CWE CWE-94
Vendor openc3
Product cosmos
Published Sep 23, 2026
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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High

Affected Versions

OpenC3 / cosmos
>= 5.1.0, < 7.3.0

References

NVD โ†— CVE.org โ†— EPSS Data โ†—
github.com: https://github.com/OpenC3/cosmos/security/advisories/GHSA-jjq7-m736-w977 github.com: https://github.com/OpenC3/cosmos/pull/3488 github.com: https://github.com/OpenC3/cosmos/commit/71943352a28128ef3e7e894319d97a656b5cd4f2 github.com: https://github.com/OpenC3/cosmos/commit/7a1538a4626f82c0d1540fcaa27ffdcbbd71ff81