OpenC3 COSMOS: Self-XSS in the Command Sender_CVE-2026-42086

4.6 / 10

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N

Description

OpenC3 COSMOS provides the functionality needed to send commands to and receive data from one or more embedded systems. Prior to version 7.0.0, the Command Sender UI uses an unsafe eval() function on array-like command parameters, which allows a user-supplied payload to execute in the browser when sending a command. This creates a self-XSS risk because an attacker can trigger their own script execution in the victim’s session, if allowed to influence the array parameter input, for example via phishing. If successful, an attacker may read or modify data in the authenticated browser context, including session tokens in local storage. This issue has been patched in version 7.0.0.

Basic Information

ID CVE-2026-42086

Source GitHub_M

Published May 4, 2026 at 17:15

Affected Product

Vendor OpenC3

Product cosmos

Version < 7.0.0

Affected Versions OpenC3 cosmos < 7.0.0

CWE Classification

CWE-79

References

github.com /OpenC3/cosmos/security/advisories/GHSA-ffq5-qpvf-xq7x

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