CVE-2026-61791CVE-2026-61791

OCO-Server is a self-hosted endpoint management application for computer inventory, software deployment, and mobile device management. Prior to 1.2.1, `Html::commandButton()` in `lib/Html.class.php` embeds an action URL containing a stored computer hostname into a JavaScript string in an inline `onclick` handler, using `htmlspecialchars(ENT_QUOTES)` only for HTML escaping. Browsers decode the HTML entities before interpreting the handler as JavaScript, allowing a crafted hostname to escape the string and execute script in an administrator's authenticated session when an affected command button is activated. `frontend/views/computer-details.php` passes `$computer->hostname` to this helper using `Computer::DEFAULT_COMPUTER_COMMANDS` in `lib/Models/Computer.class.php`, whose VNC, RDP, SSH, and Ping entries use `new_tab=false` and the vulnerable `window.location` branch. A remote attacker who possesses the shared `agent-registration-key` can use the `oco.agent.hello` handler in `frontend/a