Shenzhen TVT Digital Technology Co., Ltd. NVMS-9000 firmware (used by many white-labeled DVR/NVR/IPC products) contains hardcoded API credentials and an OS command injection flaw in its configuration services. The web/API interface accepts HTTP/XML requests authenticated with a fixed vendor credential string and passes user-controlled fields into shell execution contexts without proper argument sanitization. An unauthenticated remote attacker can leverage the hard-coded credential to access endpoints such as /editBlackAndWhiteList and inject shell metacharacters inside XML parameters, resulting in arbitrary command execution as root. The same vulnerable backend is also reachable in some models through a proprietary TCP service on port 4567 that accepts a magic GUID preface and base64-encoded XML, enabling the same command injection sink. Firmware releases from mid-February 2018 and later are reported to have addressed this issue. Exploitation evidence was observed by the Shadowserver Foundation on 2025-01-28 UTC.