Answer in brief
CVE-2026-77602 records a Critical severity (CVSS 9.9) vulnerability in OpenC3 COSMOS: Authenticated remote code execution via the user-writable config overlay (table definitions, cmd/tlm definitions, and script suites). The current sources do not mark it as known exploited. The current feed maps OpenC3/cosmos (generic), openc3 (rubygems). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 9.9. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps OpenC3/cosmos (generic), openc3 (rubygems). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| OpenC3/cosmosgeneric | >=5.1.0 <7.3.0 | 7.3.0 |
| openc3rubygems | >=5.1.0,<=7.2.1 | 7.3.0 |
Published upstream
Sep 23, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 23, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 23, 2026
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.
Quoted source text, attributed separately from HOL analysis.