Nginx Proxy Manager Authenticated RCE via setupCertbotPlugins()

Nginx Proxy Manager versions 2.9.14 through 2.15.1, fixed in commit a5db5ed, contain an authenticated remote code execution vulnerability via OS command injection in the setupCertbotPlugins() function in backend/setup.js, allowing attackers with certificates:manage permission to execute arbitrary commands by storing a malicious payload in the dns_provider_credentials field. The user-controlled dns_provider_credentials value is interpolated directly into a shell command executed via child_process.exec() without sanitization or escaping, causing the injected command to execute upon backend restart.