CVE-2026-42084: high-severity vulnerability in OpenC3 cosmos
OpenC3 COSMOS: Hijacked session token can be used to reset password for persistence
Published · Updated
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.1epss 0.3%
OpenC3 COSMOS provides the functionality needed to send commands to and receive data from one or more embedded systems. Prior to versions 6.10.5 and 7.0.0-rc3, the OpenC3 password change functionality allows a user to change their password without providing the old password, by accepting a valid session token instead. In assumed breach scenarios, this behaviour can be exploited by an attacker who has already obtained a valid session token, to gain persistence in hijacked account (including admin) and prevent legitimate users from accessing the account. This issue has been patched in versions 6.10.5 and 7.0.0-rc3.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Affected products
OpenC3 · cosmosRelated CVEs — OpenC3 cosmos
In the same product, most dangerous first.
CVE-2024-46977MEDIUMOpenC3 COSMOS allows a path traversal via screen controller (`GHSL-2024-127`)EPSS 0.9%CVE-2026-77602CRITICALOpenC3 COSMOS: Authenticated remote code execution via the user-writable config overlay (table definitions, cmd/tlm definitions, and script suites)EPSS 0.7%CVE-2025-68271CRITICALUnauthenticated Remote Code Execution in openc3-apiEPSS 0.6%CVE-2026-77601HIGHOpenC3 COSMOS: Authenticated OS command injection via the `pypi_url` settingEPSS 0.6%CVE-2024-43795MEDIUMOpenC3 COSMOS vulnerable to cross-site scripting in Login functionality (`GHSL-2024-128`)EPSS 0.5%CVE-2026-77394HIGHOpenC3 COSMOS: Stored, cross-user XSS via Telemetry screen BUTTON widgetEPSS 0.4%