CVE-2026-42084: 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…

PriorityP354high8.1CVSS 3.1

AVNACLPRLUINSUCHIHAN

EPSS

0.30%

22.1th percentile

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.

Affected

3 ranges

Vendor	Product	Version range	Fixed in
openc3	cosmos	< 6.10.5	6.10.5
openc3	cosmos	—	—
openc3	cosmos	—	—

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