CVE-2026-77394

OpenC3 COSMOS provides the functionality needed to send commands to and receive data from one or more embedded systems. From 5.0.6 until 7.3.0, an authenticated actor with system_set permission can store a shared screen through POST /openc3-api/screen whose BUTTON widget action is evaluated by openc3-cosmos-init/plugins/packages/openc3-vue-common/src/widgets/ButtonWidget.vue in another operator's browser session when the button is activated. The stored script runs in the COSMOS origin and can read localStorage.openc3Token, allowing theft of the victim's bearer token, account takeover, and actions with the victim's privileges. The permissive content security policy contributes to execution but is not the primary root cause. This issue is fixed in version 7.3.0.
Configurations

No configuration.

History

23 Sep 2026, 20:17

Type Values Removed Values Added
References () https://github.com/OpenC3/cosmos/security/advisories/GHSA-gvf2-2rh5-mpgf - () https://github.com/OpenC3/cosmos/security/advisories/GHSA-gvf2-2rh5-mpgf -

23 Sep 2026, 19:19

Type Values Removed Values Added
New CVE

Information

Published : 2026-09-23 19:19

Updated : 2026-09-23 20:17


NVD link : CVE-2026-77394

Mitre link : CVE-2026-77394

CVE.ORG link : CVE-2026-77394


JSON object : View

Products Affected

No product.

CWE
CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')