CVE-2026-77602

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

Published: Sep 23, 2026Updated: Sep 23, 2026 Sources: CVE List NVDCWE-94

9.9CRITICAL

Description

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:LPrivileges Required

Low

UI:NUser Interaction

None

Scope

S:CScope

Changed

Impact

C:HConfidentiality

High

I:HIntegrity

High

A:HAvailability

High

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Weaknesses

CWE-94

Affected Products

OpenC3

oss-project

cosmosOn-prem

OSS Libraries

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques

Execution

Initial Access

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References

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

and 1 more references View all →

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